feat: add Node.js to all runner images (golang, rust, node)

- Dockerfile.golang: docker:27-cli + Node.js + build tools
- Dockerfile.rust: docker:27-cli + Node.js + Rust + build tools
- Dockerfile.node: node:22-bookworm + docker.io (already has Node.js)
- All runners now support GitHub Actions (checkout@v4 requires Node.js)
- Images built/pushed manually (no CI for homelab)

To build and push:
  docker build -f k8s/infra/forgejo-runner/Dockerfile.golang \
    -t forgejo.riotpiao.com/rock/forgejo-runner-golang:latest .
  docker build -f k8s/infra/forgejo-runner/Dockerfile.rust \
    -t forgejo.riotpiao.com/rock/forgejo-runner-rust:latest .
  docker build -f k8s/infra/forgejo-runner/Dockerfile.node \
    -t forgejo.riotpiao.com/rock/forgejo-runner-node:latest .

  docker push forgejo.riotpiao.com/rock/forgejo-runner-golang:latest
  docker push forgejo.riotpiao.com/rock/forgejo-runner-rust:latest
  docker push forgejo.riotpiao.com/rock/forgejo-runner-node:latest

k8s/infra/forgejo-runner/values-rust.yaml

@@ -2,20 +2,16 @@
 # runner instance. Only runner.name and runner.labels differ -- everything
 # else (image, dind, persistence, tolerations, nodeSelector) is shared.
 #
-# Use docker:27-cli instead of rust:1.83-bookworm because:
-#   - Needs Node.js for GitHub Actions (actions/checkout@v4, etc.)
-#   - Has docker CLI + git + full dev tools
-#   - rust:1.83-bookworm lacks Node.js (causes action failures)
-#
-# docker:27-cli verified: docker manifest inspect docker:27-cli ✓
+# Custom image: docker:27-cli + Node.js + Rust + build tools
+#   - Node.js for GitHub Actions (actions/checkout@v4, etc.)
+#   - Docker CLI for container builds
+#   - Rust toolchain (via rustup)
+#   - Build essentials
 runner:
   name: rust-runner
-  labels: "rust:docker://docker:27-cli"
+  labels: "rust:docker://forgejo.riotpiao.com/rock/forgejo-runner-rust:latest"
+
 
-persistence:
-  reg:
-    storageClass: longhorn
-    size: 20Gi
 
 # GC CronJob renders only from the default (golang) values to avoid duplicates
 gc: