feat(apps): onboard nextcloud (Phase 6) — first CNPG-DB + OIDC-target patterns

Onboard nextcloud (docs/13 row 7): public, DR-critical file sync backed by an
external PostgreSQL. Establishes the reusable CNPG-DB pattern for later DB-backed
services.

- catalog/nextcloud.yaml: ServiceDefinition (image nextcloud:31-apache :80, public,
  internet, data 20Gi longhorn @/var/www/html, backup daily-offcluster, auth oidc
  +platform-admins, ingress nextcloud.home.keithjackson.dev, dependency
  nextcloud-db:5432). Uses schema 1.2.0 env for the Postgres connection, break-glass
  admin, trusted-domain + OVERWRITE* proxy settings.
- apps/nextcloud-db.yaml: CloudNativePG Cluster in a dedicated nextcloud-db namespace
  (modeled on keycloak-db; no default-deny, mirroring the verified keycloak posture),
  inheritedMetadata stamps app.kubernetes.io/name=nextcloud-db so the rendered egress
  CNP matches. initdb consumes a pre-provisioned owner secret.
- apps/nextcloud-db-app.sops.yaml + apps/nextcloud-bootstrap-secret.sops.yaml: SOPS
  (age) — shared DB password mirrored across the two namespaces (Pods cannot read a
  Secret cross-namespace), plus the break-glass local admin.
- apps/nextcloud.yaml: rendered manifests (catalog/render.py --no-image-automation).
- apps/kustomization.yaml: wire in the four new resources.

OIDC realm-client wiring DEFERRED (WS-APPS step-3 escape hatch): editing the reconciled
realm import in platform-config risks the running Keycloak realm / whole platform-config
apply, and nextcloud OIDC needs post-install occ steps with no first-class env — nextcloud
comes up INSTALLED on the break-glass local admin (as Gitea did); the Keycloak client is a
follow-up. Off-cluster backup awaits Velero/OQ-BKP (intent declared).

Gates: render --selftest PASS; other apps byte-identical; ci l0 17/17; l1 3/3; lint clean.

Co-Authored-By: Claude Opus 4.8 <[email protected]>

apps/nextcloud-db-app.sops.yaml

@@ -0,0 +1,36 @@
+# Nextcloud PostgreSQL owner credentials (WS-APPS, Phase 6). SOPS-encrypted (age).
+# type basic-auth (keys username/password) so the CNPG nextcloud-db Cluster consumes it as the
+# nextcloud role via spec.bootstrap.initdb.secret. The SAME password is mirrored (out of band) into
+# nextcloud-bootstrap/db-password in ns nextcloud for the app env (cross-ns Secret reads are not
+# possible). Recover: infra/devcontainer/dev.sh run sops -d apps/nextcloud-db-app.sops.yaml
+apiVersion: v1
+kind: Secret
+metadata:
+    name: nextcloud-db-app
+    namespace: nextcloud-db
+    labels:
+        app.kubernetes.io/name: nextcloud-db
+type: kubernetes.io/basic-auth
+stringData:
+    username: ENC[AES256_GCM,data:fB2YI9sNjeZj,iv:o1L0XH5bMOPODdk4cFxMMTOOCQNhAPm9aI708x4FoCE=,tag:nKrVmibWaPeJTnFN84BlSQ==,type:str]
+    password: ENC[AES256_GCM,data:09mWJL4t7yOoYsMFsoPNib7wgPJKQ3vmQudDu4+hQwDOReZTA3pgTsRkh4E//DN5,iv:nHA+fHGV6pAh+khwaBQLHgqdSjHY7U8MCDTgFWcgzEg=,tag:1zyzN4/L9LWkBZ0kjusLhg==,type:str]
+sops:
+    kms: []
+    gcp_kms: []
+    azure_kv: []
+    hc_vault: []
+    age:
+        - recipient: age175l8mdpdfu7hq0aml3exs3gykarwjmuvr23sq56s3wjejnyk44wsp4mfzg
+          enc: |
+            -----BEGIN AGE ENCRYPTED FILE-----
+            YWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSBZT3B5K3BETnlyK3JSQzV1
+            aFc4RlZBdFBza1Y1cDR1dnJJZGdySjNEY25RCkdsYVltWGlRSlQwTnRYMnFoNHZW
+            OXZWOHFYRS9RbEtmVjczRUh5V0VBZ2cKLS0tICtvSlp6YkQ3S2s4bWNLMzhKeEd2
+            K2h1TjV2aFdxdWhHZ1RqOXhTS0g3OUEKQdlDeBcuzhkCjh3ubLp8F7cn9dsqNEni
+            hYv08MMmO8xR1fTUvShloWYeg3/UnnjM/jihPKzvS9wIdv4fTY2ShA==
+            -----END AGE ENCRYPTED FILE-----
+    lastmodified: "2026-08-26T06:30:08Z"
+    mac: ENC[AES256_GCM,data:u1DrTgAtbzzIKjZwEdDYxtWSN3yFf2yCZ8u9QZZDglT7KwjNRdgckpeoNst5Qq0iGkzldKQmBeSKkOvSeMe1iFam9qKM3abcqDRbaw+cAr9XKaUgKaNKyVvaiHqNYoaWynn5GcxKfe6TrYAAxTN4kJAAk71sSzbTP0fTEO0tOKs=,iv:LiSIBo1qZ7/txIqsHEb9hnhXLZI15NOU/byLN4skL/o=,tag:oxwNBvRP77TTzwAbK8F9hA==,type:str]
+    pgp: []
+    encrypted_regex: ^(data|stringData)$
+    version: 3.9.4