fix: standardize poimen-workflows CI to unified pattern

Unified pattern enforced:
- test job: runs on all branches + PRs
- build-push job: only on main push, depends on test
- Proper env vars (GOPRIVATE, REGISTRY, IMAGE)
- Install Node.js before checkout
- Install docker only in build-push
- Docker login + build + push + prune

.gitea/workflows/ci.yaml

@@ -25,10 +25,10 @@ jobs:
       - name: Download dependencies
         run: go mod download
 
-      - name: Vet
+      - name: Go vet
         run: go vet ./...
 
-      - name: Test
+      - name: Go test
         run: go test ./...
 
       - name: Build binary
@@ -41,26 +41,39 @@ jobs:
     runs-on: golang
     steps:
       - name: Install Node.js and Docker
-        run: apt-get update && apt-get install -y nodejs docker.io
+        run: |
+          apt-get update
+          apt-get install -y nodejs docker.io
 
       - name: Checkout code
         uses: actions/checkout@v4
 
       - name: Get short SHA
         id: sha
-        run: echo "short_sha=$(git rev-parse --short HEAD)" >> $GITHUB_OUTPUT
+        run: |
+          SHORT_SHA=$(git rev-parse --short HEAD)
+          echo "short_sha=${SHORT_SHA}" >> $GITHUB_OUTPUT
 
       - name: Registry login
         run: |
-          echo "${{ secrets.FORGEJO_REGISTRY_TOKEN }}" | docker login "${REGISTRY}" \
-            --username "${{ secrets.FORGEJO_REGISTRY_USER }}" --password-stdin
+          echo "${REGISTRY_TOKEN}" | docker login "${REGISTRY}" \
+            --username "${REGISTRY_USER}" --password-stdin
+        env:
+          REGISTRY_USER: ${{ secrets.FORGEJO_REGISTRY_USER }}
+          REGISTRY_TOKEN: ${{ secrets.FORGEJO_REGISTRY_TOKEN }}
 
-      - name: Build and push image
+      - name: Build Docker image
         run: |
-          docker build \
+          docker build --no-cache \
             -t "${IMAGE}:${{ steps.sha.outputs.short_sha }}" \
             -t "${IMAGE}:latest" \
             .
+
+      - name: Push Docker image
+        run: |
           docker push "${IMAGE}:${{ steps.sha.outputs.short_sha }}"
           docker push "${IMAGE}:latest"
-          echo "✓ Pushed ${IMAGE}:${{ steps.sha.outputs.short_sha }}"
+          echo "✓ Image pushed: ${IMAGE}:${{ steps.sha.outputs.short_sha }}"
+
+      - name: Prune unused images
+        run: docker image prune -a --force 2>&1 | tail -3 || true