ci(actions): simplify docker workflow paths

- split workflow into pr-build and publish jobs
- run quick docker build only for pull requests
- keep lint and multi-arch publish on push/tag events
- add pnpm setup action and remove corepack step

.github/workflows/docker-build-push.yml

@@ -16,41 +16,17 @@ env:
   IMAGE_NAME: prototype-manager
 
 jobs:
-  docker:
+  pr-build:
+    if: github.event_name == 'pull_request'
     runs-on: ubuntu-latest
-
     steps:
       - name: Checkout
         uses: actions/checkout@v4
 
-      - name: Set up Node.js
-        if: github.event_name != 'pull_request'
-        uses: actions/setup-node@v4
-        with:
-          node-version: 22
-          cache: pnpm
-
-      - name: Enable Corepack
-        if: github.event_name != 'pull_request'
-        run: corepack enable
-
-      - name: Install dependencies
-        if: github.event_name != 'pull_request'
-        run: pnpm install --frozen-lockfile
-
-      - name: Run lint
-        if: github.event_name != 'pull_request'
-        run: pnpm lint
-
-      - name: Set up QEMU
-        if: github.event_name != 'pull_request'
-        uses: docker/setup-qemu-action@v3
-
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
 
-      - name: Build image (PR only, quick validation, no push)
-        if: github.event_name == 'pull_request'
+      - name: Build image (PR only, no push)
         uses: docker/build-push-action@v6
         with:
           context: .
@@ -59,8 +35,38 @@ jobs:
           cache-from: type=gha,scope=${{ github.ref_name }}
           cache-to: type=gha,mode=max,scope=${{ github.ref_name }}
 
+  publish:
+    if: github.event_name != 'pull_request'
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Set up pnpm
+        uses: pnpm/action-setup@v4
+        with:
+          version: 10
+          run_install: false
+
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: 22
+          cache: pnpm
+
+      - name: Install dependencies
+        run: pnpm install --frozen-lockfile
+
+      - name: Run lint
+        run: pnpm lint
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v3
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+
       - name: Log in to GHCR
-        if: github.event_name != 'pull_request'
         uses: docker/login-action@v3
         with:
           registry: ghcr.io
@@ -68,14 +74,12 @@ jobs:
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Log in to Docker Hub
-        if: github.event_name != 'pull_request'
         uses: docker/login-action@v3
         with:
           username: ${{ secrets.DOCKERHUB_USERNAME }}
           password: ${{ secrets.DOCKERHUB_TOKEN }}
 
       - name: Extract Docker metadata
-        if: github.event_name != 'pull_request'
         id: meta
         uses: docker/metadata-action@v5
         with:
@@ -90,7 +94,6 @@ jobs:
             type=raw,value=latest,enable={{is_default_branch}}
 
       - name: Build and push image (multi-arch)
-        if: github.event_name != 'pull_request'
         uses: docker/build-push-action@v6
         with:
           context: .