renovate: termix via customManagers (kubernetes manager doesn't honor inline comments)

The previous attempt (inline `# renovate:` comment in termix.yaml) silently
did nothing -- after merge + manual run, the dashboard's
`termix-system/termix.yaml (2)` was the resource count (Deployment +
Ingress), not detected updates. No PRs opened, no termix branches, no
queue entries anywhere.

Root cause: Renovate's `kubernetes` manager does NOT process inline
`# renovate:` comments. Those work for dockerfile/flux/helmfile/github-
actions/helm-values/etc., but kubernetes is missing from that list.

Correct fix: a `customManagers.regex` entry that extracts termix's image
directly with the right datasource/versioning/extractVersion set at
EXTRACTION time -- before any docker-version pre-check can reject the
prefixed tag. Plus a packageRule disabling the kubernetes manager for
termix so it doesn't silently skip the dep and clutter the dashboard.

Changes:
  - admin-system/renovate.yaml:
    * enabledManagers += "custom.regex"
    * customManagers: termix.yaml regex extraction -> github-releases
      datasource on Termix-SSH/Termix with `extractVersion=^release-(?<version>.+)$`
    * packageRules: disable kubernetes manager for ghcr.io/lukegus/termix
  - termix-system/termix.yaml: drop the useless inline comment, leave a
    NOTE explaining where the actual config lives.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

admin-system/renovate.yaml

@@ -46,10 +46,24 @@ data:
       "dependencyDashboardTitle": "Renovate Dependency Dashboard",
       "prHourlyLimit": 16,
       "prConcurrentLimit": 16,
-      "enabledManagers": ["kubernetes", "helm-values"],
+      "enabledManagers": ["kubernetes", "helm-values", "custom.regex"],
       "kubernetes": {
         "managerFilePatterns": ["/.+\\.ya?ml$/"]
       },
+      "customManagers": [
+        {
+          "description": "termix uses a release-X.Y.Z prefixed tag that the kubernetes manager's docker-versioning pre-check rejects (so no PRs are ever created). This customManager extracts the image directly, redirects the version lookup to GitHub Releases at Termix-SSH/Termix (which exposes timestamps the 3-day stability gate needs), and uses extractVersion to strip the `release-` prefix so loose semver can parse it.",
+          "customType": "regex",
+          "managerFilePatterns": ["/termix-system/.+\\.ya?ml$/"],
+          "matchStrings": [
+            "image:\\s+(?<depName>ghcr\\.io/lukegus/termix):(?<currentValue>release-\\d+\\.\\d+\\.\\d+)"
+          ],
+          "datasourceTemplate": "github-releases",
+          "packageNameTemplate": "Termix-SSH/Termix",
+          "versioningTemplate": "loose",
+          "extractVersionTemplate": "^release-(?<version>.+)$"
+        }
+      ],
       "packageRules": [
         {
           "description": "All apps: 3-day stability gate before any PR opens",
@@ -94,6 +108,12 @@ data:
           "description": "wanderer: db + web update together in one PR",
           "matchPackageNames": ["flomp/wanderer-db", "flomp/wanderer-web"],
           "groupName": "wanderer"
+        },
+        {
+          "description": "termix: kubernetes manager would extract the image with versioning=docker and silently skip it (release-1.11.0 fails the docker pre-check). Disable that extraction; customManagers above does the real work via github-releases.",
+          "matchManagers": ["kubernetes"],
+          "matchPackageNames": ["ghcr.io/lukegus/termix"],
+          "enabled": false
         }
       ],
       "labels": ["renovate"]

termix-system/termix.yaml

@@ -41,7 +41,10 @@ spec:
     spec:
       containers:
         - name: termix
-          # renovate: datasource=github-releases depName=Termix-SSH/Termix versioning=loose extractVersion=^release-(?<version>.+)$
+          # NOTE: termix uses a non-semver tag pattern (release-X.Y.Z).
+          # Renovate handles it via a customManagers regex defined in
+          # admin-system/renovate.yaml (the kubernetes manager doesn't
+          # process inline `# renovate:` comments).
           image: ghcr.io/lukegus/termix:release-1.11.0
           imagePullPolicy: IfNotPresent
           ports: