fix: Forgejo CI runners — proper images, shared docker socket, auto-registration

All CI workflows across all repos were broken. Three root causes:

1. Runner labels pointed to bare Alpine image (forgejo/runner:6) which has
   no Node.js, no docker, no Go/Rust, no root, no apt-get. Every workflow
   step failed immediately.

   Fix: Change labels to official Debian language images:
     golang → docker://golang:1.26-bookworm
     node   → docker://node:22-bookworm
     rust   → docker://rust:1-bookworm

2. Docker socket not shared between dind sidecar and runner container.
   dind creates /run/docker.sock in its own filesystem. Runner container
   has a separate filesystem and can't see it. Workflow containers that
   run 'docker build' get 'Cannot connect to Docker daemon'.

   Fix: Share /run between dind and runner via emptyDir volume.
   Add docker_host: automount to runner config so the socket is
   mounted into workflow containers automatically.

   Note: /var/run is a symlink to /run in Alpine — must mount at /run.

3. Init container skipped re-registration if .runner file existed on PVC.
   Changing labels in values.yaml had no effect until PVC was manually
   deleted — not GitOps-friendly.

   Fix: Always rm .runner and re-register on pod start. Labels stay
   in sync with values.yaml automatically.

Also removes custom Dockerfiles and build-runner-images workflow — no longer
needed since official images provide the language tools directly.

k8s/infra/forgejo-runner/Dockerfile.golang

@@ -1,12 +0,0 @@
-FROM code.forgejo.org/forgejo/runner:6
-
-# Install Node.js + Docker client (needed for GitHub Actions + docker build)
-RUN apt-get update && \
-    apt-get install -y --no-install-recommends \
-      nodejs \
-      npm \
-      docker.io && \
-    rm -rf /var/lib/apt/lists/*
-
-# Verify installations
-RUN docker --version && node --version && git --version

k8s/infra/forgejo-runner/Dockerfile.node

@@ -1,11 +0,0 @@
-FROM code.forgejo.org/forgejo/runner:6
-
-# Install Docker client (forgejo/runner base doesn't include it)
-RUN apt-get update && \
-    apt-get install -y --no-install-recommends \
-      docker.io && \
-    rm -rf /var/lib/apt/lists/*
-
-# Verify installations
-RUN node --version && docker --version && git --version
-# Trigger node-runner build with docker

k8s/infra/forgejo-runner/Dockerfile.rust

@@ -1,16 +0,0 @@
-FROM code.forgejo.org/forgejo/runner:6
-
-# Install Node.js + Rust (needed for GitHub Actions checkout@v4, etc.)
-RUN apt-get update && \
-    apt-get install -y --no-install-recommends \
-      nodejs \
-      npm && \
-    rm -rf /var/lib/apt/lists/*
-
-# Install Rust
-RUN curl --proto '=https' --tlsv1.2 -sSf https://sh.rustup.rs | sh -s -- -y
-
-ENV PATH="/root/.cargo/bin:${PATH}"
-
-# Verify installations
-RUN docker --version && node --version && git --version && rustc --version

k8s/infra/forgejo-runner/templates/configmap.yaml

@@ -36,3 +36,4 @@ data:
       valid_volumes:
         - /docker-certs/client
       network: host
+      docker_host: automount

k8s/infra/forgejo-runner/templates/deployment.yaml

@@ -34,7 +34,11 @@ spec:
           command: ["sh", "-c"]
           args:
             - |
-              test -f /data/.runner || forgejo-runner register --no-interactive \
+              # Always re-register to keep labels in sync with values.yaml.
+              # Without this, changing a runner label requires manually deleting
+              # the PVC or .runner file — not GitOps-friendly.
+              rm -f /data/.runner
+              forgejo-runner register --no-interactive \
                 --instance {{ .Values.runner.forgejoUrl }} \
                 --token $(RUNNER_TOKEN) \
                 --name {{ .Values.runner.name }} \
@@ -70,6 +74,8 @@ spec:
               mountPath: /data
             - name: docker-certs
               mountPath: /docker-certs
+            - name: docker-sock
+              mountPath: /run
             - name: homelab-ca
               mountPath: /etc/ssl/certs/homelab-ca.pem
               subPath: ca.crt
@@ -89,6 +95,8 @@ spec:
           volumeMounts:
             - name: docker-certs
               mountPath: /docker-certs
+            - name: docker-sock
+              mountPath: /run
             - name: dind-storage
               mountPath: /var/lib/docker
             - name: homelab-ca
@@ -113,6 +121,8 @@ spec:
             claimName: {{ .Release.Name }}-dind
         - name: docker-certs
           emptyDir: {}    # DinD regenerates mTLS certs on each start
+        - name: docker-sock
+          emptyDir: {}    # Shared docker socket between dind and runner
         - name: homelab-ca
           # homelab-ca is a ConfigMap (public CA trust bundle), not a Secret.
           # The volumeMounts use subPath: ca.crt to project the single cert file.

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

@@ -2,15 +2,14 @@
 # runner instance. Only runner.name and runner.labels differ -- everything
 # else (image, dind, persistence, tolerations, nodeSelector) is shared.
 #
-# node:22-bookworm ships Node natively. Docker client installed via workflow step if needed.
-# (homelab has no CI; custom runner images built manually if desired)
-# Bootstrap with runner image (already has Node.js), CI builds custom
+# Label image: node:22-bookworm — Debian, root, apt-get, Node.js, npm, git.
+# Install docker in workflow steps as needed.
 runner:
   image:
     repository: code.forgejo.org/forgejo/runner
     tag: "6"
   name: node-runner
-  labels: "node:docker://code.forgejo.org/forgejo/runner:6"
+  labels: "node:docker://node:22-bookworm"
 
 # GC CronJob renders only from the default (golang) values to avoid duplicates
 gc:

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

@@ -2,13 +2,14 @@
 # runner instance. Only runner.name and runner.labels differ -- everything
 # else (image, dind, persistence, tolerations, nodeSelector) is shared.
 #
-# Bootstrap with runner image, CI builds custom with Node.js+Rust
+# Label image: rust:1-bookworm — Debian, root, apt-get, Rust, cargo, git.
+# Install Node.js/docker in workflow steps as needed.
 runner:
   image:
     repository: code.forgejo.org/forgejo/runner
     tag: "6"
   name: rust-runner
-  labels: "rust:docker://code.forgejo.org/forgejo/runner:6"
+  labels: "rust:docker://rust:1-bookworm"
 
 
 

k8s/infra/forgejo-runner/values.yaml

@@ -1,9 +1,12 @@
 runner:
   image:
     repository: code.forgejo.org/forgejo/runner
-    tag: "6"  # Bootstrap with runner image, CI builds custom with Node.js
+    tag: "6"
   name: golang-runner
-  labels: "golang:docker://code.forgejo.org/forgejo/runner:6"
+  # Label image is what workflow steps run in (NOT the runner daemon image).
+  # golang:1.26-bookworm: Debian, root, apt-get, Go, git.
+  # Install Node.js/docker in workflow steps as needed.
+  labels: "golang:docker://golang:1.26-bookworm"
   forgejoUrl: http://forgejo-gitea-http.cicd.svc.cluster.local:3000
   tokenSecret: runner-token
   resources: