feat(dns): per-environment BASE_DOMAIN — prod moves to its own subdomain

INCIDENT FIX. Prod's external-dns DELETED EVERY ONE OF DEV'S PUBLIC DNS RECORDS. Both
clusters ran policy: sync against the SAME Cloudflare zone with the SAME implicit
txtOwnerId (`default`), so prod believed it owned dev's records, found no matching sources,
and removed them plus their TXT registry entries. Dev recovered ~30s after prod was scaled
to 0; verified restored against Cloudflare directly (my first check went through a pfSense
override and falsely showed healthy — local resolvers are not evidence about public DNS).

THE MISS WAS MINE, and it was a failure of imagination in how I briefed every agent. I put
"never touch dev" in brief after brief and enforced it — separate kubeconfigs, verified
--limit, sha-checked dev's kubeconfig before and after. Every one of those guards held. NONE
of them covered SHARED EXTERNAL RESOURCES. Prod reconciling its OWN correctly-authored
manifests reached across a third party and destroyed dev's state. Cluster-to-cluster
isolation was verified; the dependency that mattered was cluster-to-Cloudflare.

Operator's architecture: dev -> *.dev.home.keithjackson.dev, prod ->
*.prod.home.keithjackson.dev, apex CNAME <svc>.home -> <svc>.prod.home.

PHASE 1 ONLY (this commit): prod moves to its own subdomain. DEV IS NOT MIGRATED and its
effective hostname stays home.keithjackson.dev, so dev renders byte-identically and nothing
live moves. That alone ends the collision and unblocks prod. Phase 2 (dev -> dev.home. +
apex CNAMEs) is deferred to when the operator is present: it relocates Keycloak's issuer and
12 clients' redirect URIs, forces a rolling k3s restart and kubectl SSO re-issue for every
user, and moves gitea.home. — which is BOTH the GitOps source and the current push target.

BASE_DOMAIN WAS A DEAD KNOB — it existed in cluster-vars but the status report flagged it as
referenced by nothing, because hostnames were hardcoded throughout. Now real: 141 refs.
Searched the AUTHORITATIVE reconciled set by resolving each Flux spec.path transitively via
conformance/lib/status.py — the same resolver the L0 gate uses, so "what Flux reconciles"
has one definition. 185 occurrences across 47 files in 154 reconciled files. Tokenized:
Gateway listeners, the wildcard Certificate, coredns-custom, external-dns, Keycloak
instance/realm (26 redirect URIs), oauth2-proxy, Grafana OIDC, all HTTPRoutes, Homepage's 15
links, 30 runbook_urls, unifi cloud-init, render.py's ZONE constant (which drove
--oidc-issuer-url/--cookie-domain/--whitelist-domain on every forward-auth sidecar) and 11
catalog/ ServiceDefinitions re-rendered canonically. Left alone: 43 comment/prose
occurrences and non-reconciled paths.

TWO THAT CANNOT BE TOKENIZED, flagged not forced:
  - headlamp's OIDC URLs live inside a SOPS-encrypted Secret; re-encrypting rewrites the MAC
    over every value and the OFFLINE harness cannot verify it (kustomize does not decrypt),
    so an error would break live-dev SSO with no pre-flight proof. Prod needs its own copy
    anyway — client secrets are realm-scoped.
  - kube-apiserver --oidc-issuer-url is a k3s SERVER FLAG, not a manifest, so Flux can never
    reach it. Done on the inventory seam instead (k3s_base_domain -> k3s_oidc_issuer_url,
    overridden in group_vars/k3s_prod). Verified per host: dev keeps the default, prod gets
    prod.home.

EXTERNAL-DNS OWNER, the actual incident cause: txtOwnerId is now explicit per environment —
dev renders exactly `default` (the chart default it was already using, so its existing
records stay recognised) and prod gets `prod`. The BASE default is a NON-COLLIDING SENTINEL,
deliberately not `default`, so a future environment that forgets the knob owns nothing and
can delete nothing rather than silently inheriting dev's identity.

I OVERRODE ONE AGENT DECISION against our own prior finding: it narrowed prod's
domainFilters to prod.home.keithjackson.dev as defence in depth. FINDING F-DNS1
(DECISIONS-LOG 2026-08-17) already proved a subdomain filter DROPS THE PARENT ZONE —
ExternalDNS generates the record then skips it with "no hosted zone matching record DNS
Name". Prod would have published NOTHING. Set to the ZONE (keithjackson.dev) like dev.
Isolation comes from the subdomain split plus txtOwnerId, which is what the incident
actually needed and what a domain filter cannot provide.

DEV PROVEN UNCHANGED: 11 of 12 substituting paths byte-identical; the 12th differs by
exactly one line, `+ txtOwnerId: default` — the value dev was already using implicitly.
POSITIVE CONTROLS confirm the harness is not blind: perturbing BASE_DOMAIN moves 10 of 12
hashes (the 2 that don't provably contain no hostname), perturbing the owner id moves
exactly 1. Prod's rendered output has ZERO home.keithjackson.dev references outside prod.,
and its cert renders *.prod.home.keithjackson.dev — no overlap with dev's.

L0 substitution assertions 106 -> 254; BASE_DOMAIN is no longer flagged dead. Gate PASS.

PROD REMAINS SUSPENDED (platform + 10 downstream tiers) pending review; nothing applied.

Serves: R-ENV-02, R-DNS-01, R-DNS-02, R-DNS-03, R-TLS-01.

Co-Authored-By: Claude Opus 5 (1M context) <[email protected]>

apps/wave-0/gitea.yaml

@@ -90,9 +90,9 @@ spec:
               name: gitea-bootstrap
               key: secret-key
         - name: GITEA__server__DOMAIN
-          value: gitea.home.keithjackson.dev
+          value: gitea.${BASE_DOMAIN}
         - name: GITEA__server__ROOT_URL
-          value: https://gitea.home.keithjackson.dev/
+          value: https://gitea.${BASE_DOMAIN}/
         - name: GITEA__actions__ENABLED
           value: 'true'
         - name: GITEA__actions__DEFAULT_ACTIONS_URL
@@ -127,7 +127,7 @@ spec:
               command:
               - /bin/sh
               - -c
-              - "# Idempotent break-glass admin bootstrap. Runs alongside the gitea entrypoint\n# (which, with INSTALL_LOCK=true, headless-installs + migrates the DB on first\n# boot). Waits for the DB, then creates the admin only if it does not exist.\nset -u\nexport HOME=/data/git\ni=0\nuntil su-exec git gitea admin user list >/dev/null 2>&1; do\n  i=$((i + 1))\n  [ \"$i\" -ge 150 ] && { echo \"[gitea-bootstrap] DB not ready after wait; skipping\" >&2; exit 0; }\n  sleep 2\ndone\nif su-exec git gitea admin user list --admin 2>/dev/null | awk 'NR>1{print $2}' | grep -qx \"$GITEA_ADMIN_USERNAME\"; then\n  echo \"[gitea-bootstrap] admin '$GITEA_ADMIN_USERNAME' already present\"\nelse\n  n=0\n  until su-exec git gitea admin user create \\\n    --username \"$GITEA_ADMIN_USERNAME\" \\\n    --password \"$GITEA_ADMIN_PASSWORD\" \\\n    --email \"[email protected]\" \\\n    --admin --must-change-password=false; do\n    n=$((n + 1))\n    [ \"$n\" -ge 10 ] && { echo \"[gitea-bootstrap] admin create failed after retries\" >&2; break; }\n    sleep 3\n  done\n  echo \"[gitea-bootstrap] created break-glass admin '$GITEA_ADMIN_USERNAME'\"\nfi\n# --- Keycloak OIDC login source (idempotent add-or-update; R-IDP-02/06) ---\n# Registers the confidential `gitea` client as the OAuth2 login source \"keycloak\" against the\n# homelab realm's discovery doc. The `groups` claim maps platform-admins -> Gitea admin\n# (--admin-group). Missing secret => skip (break-glass admin still works), so an unfilled\n# secret never crashes the pod.\n#\n# HARDENED (was a silent first-boot RACE): this step used to fire before the app/network was\n# ready and swallow its failure (|| echo ... >&2, exit 0), so SSO silently never registered.\n# Now it (1) waits \u2014 bounded, ~90s \u2014 for the Keycloak discovery doc to serve HTTP 200,\n# (2) registers (update-in-place if present, else create), (3) VERIFIES the source actually\n# persisted and retries the whole cycle, and (4) on give-up logs LOUDLY to stderr AND a marker\n# file on the persistent /data volume WITHOUT crashlooping the pod (break-glass admin stays\n# usable). The verify-then-retry loop is the real guarantee against \"exit 0 but nothing stuck\".\nGITEA_DISCOVERY_URL=https://keycloak.home.keithjackson.dev/realms/homelab/.well-known/openid-configuration\ngitea_oidc_fail() {\n  echo \"[gitea-oidc] FAILED to register 'keycloak' login source: $1\" >&2\n  { echo \"$(date -u +%Y-%m-%dT%H:%M:%SZ) [gitea-oidc] FAILED: $1\"; } >> /data/gitea-oidc-bootstrap.log 2>/dev/null || true\n}\n# NOTE the `$$` escape below \u2014 it is load-bearing. apps-wave-0 declares postBuild.\n# substituteFrom cluster-vars, so Flux envsubst rewrites this whole manifest at RECONCILE\n# time, before any container runs. Written unescaped, `$${GITEA_OIDC_CLIENT_SECRET:-}` is not\n# a cluster-var, so envsubst blanked it and the guard reconciled as `[ -z \"\" ]` \u2014 ALWAYS TRUE\n# \u2014 making every line below (discovery wait, add/update-oauth, verify-then-retry) DEAD CODE on\n# every boot since 8738871 (2026-08-27). SSO kept working only because the login source was\n# already in the DB; a PVC rebuild or fresh cluster would have come up with NO OIDC at all.\n# Flux STRICT substitution cannot catch this \u2014 it EXEMPTS default-operator forms by design.\n# `$${VAR}` is the escape: envsubst emits it back as a plain brace expansion for the shell.\n# Bare `$VAR` and `$(cmd)` are left alone and need NO escaping \u2014 which is why the\n# `$GITEA_OIDC_CLIENT_SECRET` uses below always worked and only the guards broke.\n# Contract: clusters/base/apps-vms.yaml. Enforced at render time by catalog/render.py.\nif [ -z \"$${GITEA_OIDC_CLIENT_SECRET:-}\" ]; then\n  echo \"[gitea-oidc] GITEA_OIDC_CLIENT_SECRET unset; skipping OIDC source (break-glass admin only)\"\nelse\n  # (1) Wait up to ~90s for the Keycloak discovery doc to be reachable (HTTP 200).\n  d=0; disc_ok=0\n  while [ \"$d\" -lt 45 ]; do\n    if [ \"$(curl -sS -o /dev/null -w '%{http_code}' --max-time 5 \"$GITEA_DISCOVERY_URL\" 2>/dev/null)\" = \"200\" ]; then\n      disc_ok=1;\
+              - "# Idempotent break-glass admin bootstrap. Runs alongside the gitea entrypoint\n# (which, with INSTALL_LOCK=true, headless-installs + migrates the DB on first\n# boot). Waits for the DB, then creates the admin only if it does not exist.\nset -u\nexport HOME=/data/git\ni=0\nuntil su-exec git gitea admin user list >/dev/null 2>&1; do\n  i=$((i + 1))\n  [ \"$i\" -ge 150 ] && { echo \"[gitea-bootstrap] DB not ready after wait; skipping\" >&2; exit 0; }\n  sleep 2\ndone\nif su-exec git gitea admin user list --admin 2>/dev/null | awk 'NR>1{print $2}' | grep -qx \"$GITEA_ADMIN_USERNAME\"; then\n  echo \"[gitea-bootstrap] admin '$GITEA_ADMIN_USERNAME' already present\"\nelse\n  n=0\n  until su-exec git gitea admin user create \\\n    --username \"$GITEA_ADMIN_USERNAME\" \\\n    --password \"$GITEA_ADMIN_PASSWORD\" \\\n    --email \"[email protected]\" \\\n    --admin --must-change-password=false; do\n    n=$((n + 1))\n    [ \"$n\" -ge 10 ] && { echo \"[gitea-bootstrap] admin create failed after retries\" >&2; break; }\n    sleep 3\n  done\n  echo \"[gitea-bootstrap] created break-glass admin '$GITEA_ADMIN_USERNAME'\"\nfi\n# --- Keycloak OIDC login source (idempotent add-or-update; R-IDP-02/06) ---\n# Registers the confidential `gitea` client as the OAuth2 login source \"keycloak\" against the\n# homelab realm's discovery doc. The `groups` claim maps platform-admins -> Gitea admin\n# (--admin-group). Missing secret => skip (break-glass admin still works), so an unfilled\n# secret never crashes the pod.\n#\n# HARDENED (was a silent first-boot RACE): this step used to fire before the app/network was\n# ready and swallow its failure (|| echo ... >&2, exit 0), so SSO silently never registered.\n# Now it (1) waits \u2014 bounded, ~90s \u2014 for the Keycloak discovery doc to serve HTTP 200,\n# (2) registers (update-in-place if present, else create), (3) VERIFIES the source actually\n# persisted and retries the whole cycle, and (4) on give-up logs LOUDLY to stderr AND a marker\n# file on the persistent /data volume WITHOUT crashlooping the pod (break-glass admin stays\n# usable). The verify-then-retry loop is the real guarantee against \"exit 0 but nothing stuck\".\nGITEA_DISCOVERY_URL=https://keycloak.${BASE_DOMAIN}/realms/homelab/.well-known/openid-configuration\ngitea_oidc_fail() {\n  echo \"[gitea-oidc] FAILED to register 'keycloak' login source: $1\" >&2\n  { echo \"$(date -u +%Y-%m-%dT%H:%M:%SZ) [gitea-oidc] FAILED: $1\"; } >> /data/gitea-oidc-bootstrap.log 2>/dev/null || true\n}\n# NOTE the `$$` escape below \u2014 it is load-bearing. apps-wave-0 declares postBuild.\n# substituteFrom cluster-vars, so Flux envsubst rewrites this whole manifest at RECONCILE\n# time, before any container runs. Written unescaped, `$${GITEA_OIDC_CLIENT_SECRET:-}` is not\n# a cluster-var, so envsubst blanked it and the guard reconciled as `[ -z \"\" ]` \u2014 ALWAYS TRUE\n# \u2014 making every line below (discovery wait, add/update-oauth, verify-then-retry) DEAD CODE on\n# every boot since 8738871 (2026-08-27). SSO kept working only because the login source was\n# already in the DB; a PVC rebuild or fresh cluster would have come up with NO OIDC at all.\n# Flux STRICT substitution cannot catch this \u2014 it EXEMPTS default-operator forms by design.\n# `$${VAR}` is the escape: envsubst emits it back as a plain brace expansion for the shell.\n# Bare `$VAR` and `$(cmd)` are left alone and need NO escaping \u2014 which is why the\n# `$GITEA_OIDC_CLIENT_SECRET` uses below always worked and only the guards broke.\n# Contract: clusters/base/apps-vms.yaml. Enforced at render time by catalog/render.py.\nif [ -z \"$${GITEA_OIDC_CLIENT_SECRET:-}\" ]; then\n  echo \"[gitea-oidc] GITEA_OIDC_CLIENT_SECRET unset; skipping OIDC source (break-glass admin only)\"\nelse\n  # (1) Wait up to ~90s for the Keycloak discovery doc to be reachable (HTTP 200).\n  d=0; disc_ok=0\n  while [ \"$d\" -lt 45 ]; do\n    if [ \"$(curl -sS -o /dev/null -w '%{http_code}' --max-time 5 \"$GITEA_DISCOVERY_URL\" 2>/dev/null)\" = \"200\" ]; then\n      disc_ok=1;\
                 \ break\n    fi\n    d=$((d + 1)); sleep 2\n  done\n  [ \"$disc_ok\" = 1 ] || gitea_oidc_fail \"Keycloak discovery endpoint not reachable (HTTP 200) within timeout\"\n  # (2)+(3) Register (update-in-place or create) then VERIFY it persisted; retry the whole cycle.\n  r=0; reg_ok=0\n  while [ \"$r\" -lt 10 ]; do\n    oidc_id=$(su-exec git gitea admin auth list 2>/dev/null | awk '$2==\"keycloak\"{print $1; exit}')\n    if [ -n \"$oidc_id\" ]; then\n      su-exec git gitea admin auth update-oauth --id \"$oidc_id\" \\\n        --name keycloak --provider openidConnect --key gitea \\\n        --secret \"$GITEA_OIDC_CLIENT_SECRET\" \\\n        --auto-discover-url \"$GITEA_DISCOVERY_URL\" \\\n        --scopes \"openid email profile\" --group-claim-name groups --admin-group platform-admins >/dev/null 2>&1 || true\n    else\n      su-exec git gitea admin auth add-oauth \\\n        --name keycloak --provider openidConnect --key gitea \\\n        --secret \"$GITEA_OIDC_CLIENT_SECRET\" \\\n        --auto-discover-url \"$GITEA_DISCOVERY_URL\" \\\n        --scopes \"openid email profile\" --group-claim-name groups --admin-group platform-admins >/dev/null 2>&1 || true\n    fi\n    # VERIFY: the \"keycloak\" source must actually be listed now (guards the exit-0-but-nothing-persisted race).\n    if su-exec git gitea admin auth list 2>/dev/null | awk '$2==\"keycloak\"{f=1} END{exit !f}'; then\n      reg_ok=1; break\n    fi\n    r=$((r + 1)); sleep 3\n  done\n  if [ \"$reg_ok\" = 1 ]; then\n    echo \"[gitea-oidc] login source 'keycloak' registered and verified\"\n  else\n    gitea_oidc_fail \"add/update-oauth ran but the 'keycloak' source did not persist after retries\"\n  fi\nfi\n# A postStart hook MUST exit 0 \u2014 a non-zero exit makes the kubelet KILL the container\n# (FailedPostStartHook -> CrashLoopBackOff). This hook already ends 0 on both paths, but\n# it is made EXPLICIT so the guarantee does not depend on whatever statement happens to\n# be last. nextcloud's equivalent hook did depend on that and crashlooped on 2026-09-01,\n# the moment its OIDC guard was fixed and the block actually ran for the first time.\nexit 0\n"
       volumes:
       - name: data
@@ -207,7 +207,7 @@ spec:
     namespace: gateway
     sectionName: https
   hostnames:
-  - gitea.home.keithjackson.dev
+  - gitea.${BASE_DOMAIN}
   rules:
   - matches:
     - path:

apps/wave-0/jackett.yaml

@@ -91,16 +91,16 @@ spec:
         - --http-address=0.0.0.0:4180
         - --reverse-proxy=true
         - --provider=oidc
-        - --oidc-issuer-url=https://keycloak.home.keithjackson.dev/realms/homelab
+        - --oidc-issuer-url=https://keycloak.${BASE_DOMAIN}/realms/homelab
         - --upstream=http://127.0.0.1:9117
         - --email-domain=*
         - --scope=openid email profile
         - --oidc-groups-claim=groups
         - --allowed-group=media-users
         - --skip-provider-button=true
-        - --redirect-url=https://jackett.home.keithjackson.dev/oauth2/callback
-        - --cookie-domain=.home.keithjackson.dev
-        - --whitelist-domain=.home.keithjackson.dev
+        - --redirect-url=https://jackett.${BASE_DOMAIN}/oauth2/callback
+        - --cookie-domain=.${BASE_DOMAIN}
+        - --whitelist-domain=.${BASE_DOMAIN}
         - --cookie-secure=true
         - --pass-access-token=true
         - --set-xauthrequest=true
@@ -273,7 +273,7 @@ spec:
     namespace: gateway
     sectionName: https
   hostnames:
-  - jackett.home.keithjackson.dev
+  - jackett.${BASE_DOMAIN}
   rules:
   - matches:
     - path:

apps/wave-0/pihole.yaml

@@ -91,16 +91,16 @@ spec:
         - --http-address=0.0.0.0:4180
         - --reverse-proxy=true
         - --provider=oidc
-        - --oidc-issuer-url=https://keycloak.home.keithjackson.dev/realms/homelab
+        - --oidc-issuer-url=https://keycloak.${BASE_DOMAIN}/realms/homelab
         - --upstream=http://127.0.0.1:80
         - --email-domain=*
         - --scope=openid email profile
         - --oidc-groups-claim=groups
         - --allowed-group=platform-admins
         - --skip-provider-button=true
-        - --redirect-url=https://pihole.home.keithjackson.dev/oauth2/callback
-        - --cookie-domain=.home.keithjackson.dev
-        - --whitelist-domain=.home.keithjackson.dev
+        - --redirect-url=https://pihole.${BASE_DOMAIN}/oauth2/callback
+        - --cookie-domain=.${BASE_DOMAIN}
+        - --whitelist-domain=.${BASE_DOMAIN}
         - --cookie-secure=true
         - --pass-access-token=true
         - --set-xauthrequest=true
@@ -229,7 +229,7 @@ spec:
     namespace: gateway
     sectionName: https
   hostnames:
-  - pihole.home.keithjackson.dev
+  - pihole.${BASE_DOMAIN}
   rules:
   - matches:
     - path:

apps/wave-0/plex.yaml

@@ -183,7 +183,7 @@ spec:
     namespace: gateway
     sectionName: https
   hostnames:
-  - plex.home.keithjackson.dev
+  - plex.${BASE_DOMAIN}
   rules:
   - matches:
     - path:

apps/wave-0/qbittorrent.yaml

@@ -91,16 +91,16 @@ spec:
         - --http-address=0.0.0.0:4180
         - --reverse-proxy=true
         - --provider=oidc
-        - --oidc-issuer-url=https://keycloak.home.keithjackson.dev/realms/homelab
+        - --oidc-issuer-url=https://keycloak.${BASE_DOMAIN}/realms/homelab
         - --upstream=http://127.0.0.1:8080
         - --email-domain=*
         - --scope=openid email profile
         - --oidc-groups-claim=groups
         - --allowed-group=media-users
         - --skip-provider-button=true
-        - --redirect-url=https://qbittorrent.home.keithjackson.dev/oauth2/callback
-        - --cookie-domain=.home.keithjackson.dev
-        - --whitelist-domain=.home.keithjackson.dev
+        - --redirect-url=https://qbittorrent.${BASE_DOMAIN}/oauth2/callback
+        - --cookie-domain=.${BASE_DOMAIN}
+        - --whitelist-domain=.${BASE_DOMAIN}
         - --cookie-secure=true
         - --pass-access-token=true
         - --set-xauthrequest=true
@@ -273,7 +273,7 @@ spec:
     namespace: gateway
     sectionName: https
   hostnames:
-  - qbittorrent.home.keithjackson.dev
+  - qbittorrent.${BASE_DOMAIN}
   rules:
   - matches:
     - path: