feat(cloudflared): Cloudflare Tunnel connector, Phase 1 (isolated, no traffic change)

Adds platform/cloudflared: a locally-managed tunnel whose ingress rules live in
git. LAN/VPN-only hosts (plex, plex-vip, jackett, pihole, pihole-dns, semaphore,
qbittorrent, radarr, sonarr, headlamp, unifi, crafty-mc) map to 404. The apex
and *.home go to cilium-gateway-shared.gateway over TLS with matchSNItoHost.
Last comes a catch-all 404. Nothing routes to the Kubernetes API.

- 2-replica Deployment, hard node spread, non-root, pinned digest, PDB
- default-deny plus an egress CNP: Cloudflare edge 7844/443, the Gateway, and
  Gateway backends by gateway-access=shared minus the LAN-only namespaces
  (needed because of the CVE-2025-30162 L7LB egress re-check)
- PodMonitor plus two alerts that fire on absent series, with promtool tests
- its own Flux Kustomization (dependsOn platform-config, wait:false, nothing
  depends on it), plus SOPS decryption patches in both overlays
- placeholder credentials (SOPS-encrypted) so it can merge before enrolment
- L0 cloudflared-ingress-rules, and a cloudflared_ scrape owner
- runbooks/cloudflare-tunnel.md and decisions/2026-11-08-cloudflare-tunnel.md

Co-Authored-By: Claude Opus 5.5 <[email protected]>

platform/cloudflared/cloudflared-credentials.sops.yaml

@@ -0,0 +1,32 @@
+# Cloudflare Tunnel credentials for platform/cloudflared — SOPS-ENCRYPTED (R-SEC-01, spec docs/07).
+# Keys stay cleartext for reviewable diffs; only `stringData` values are encrypted (.sops.yaml
+# `encrypted_regex`). Plaintext template + operator hand-off: cloudflared-credentials.sops.yaml.example.
+# Shipped with REPLACE-ME placeholders; runbooks/cloudflare-tunnel.md step 4 fills it.
+apiVersion: v1
+kind: Secret
+metadata:
+    name: cloudflared-credentials
+    namespace: cloudflared
+type: Opaque
+stringData:
+    credentials.json: ENC[AES256_GCM,data:PM5pgIW/JEUMLuhApkPhgMOkJCL0nrlgLBb3tG+pHdm8JWdNK2yYCZUWM3USY7Uy2IYphZh35RwPOrWSUCyBlSq+TeEKBkzTTgJhp4gqaQ==,iv:Sr0Z6d9LmHvGN5oebIf+YBbFyLIdNOi80d6WwOF3PtU=,tag:Enb5/9v7H1nu2kvh4zEjXg==,type:str]
+sops:
+    kms: []
+    gcp_kms: []
+    azure_kv: []
+    hc_vault: []
+    age:
+        - recipient: age175l8mdpdfu7hq0aml3exs3gykarwjmuvr23sq56s3wjejnyk44wsp4mfzg
+          enc: |
+            -----BEGIN AGE ENCRYPTED FILE-----
+            YWdlLWVuY3J5cHRpb24ub3JnL3YxCi0+IFgyNTUxOSBUanIxelFEUDZtWU5CMHd5
+            VHl5MkJnM1JDUWhkM2daY0dtRUlFUmNUMDJrClM5UFBsdjh2Q0NIWmxpM1djYXUy
+            OFlZYVdBbURLanRRNzV1RVNmbkxWR28KLS0tIFE3d1Z1MjFZMTlaTFFIWm5ndVpN
+            emhHaFpEZWpMN0JXL2NVaW5PU1ZwVW8KkCDX7ED039X12BCmiSqHr0fmZKSZmfjP
+            DIiR6DvWWw1TcB3CjD5q29nIthCDf9zlrpuMfQ+9ODAlRr5t6zP+cg==
+            -----END AGE ENCRYPTED FILE-----
+    lastmodified: "2026-11-08T18:28:24Z"
+    mac: ENC[AES256_GCM,data:RGiftdP4Bd5Qwyfx/pXEyZTBzTvr5Tvc7k0foEzTQGiSg6p0meurwtmCe/gMjKUZLhwf/0xqi1DtPQGS6UY8m8YFq1v1nXtohUQWLPXgTukMT915tHmohZeG91wYdyG9kA5E03udn+QNdOiI8OtjKoqAtifBoymCYd/EDOzWLQU=,iv:0vDIoDJ4QGECq7YjUPIlsU1j/AHfr1W32/+RjEOfpWo=,tag:BWT7nxiUxkVhEDh0JiE1Eg==,type:str]
+    pgp: []
+    encrypted_regex: ^(data|stringData)$
+    version: 3.9.4