ci: pin GitHub Actions version comments to full semver

Renovate's helpers:pinGitHubActionDigestsToSemver preset reads version
comments to track updates. Major-only comments (e.g. # v6) produce
unhelpful changelog diffs like "v6 → v6". Full semver comments
(e.g. # v6.0.2) let Renovate show meaningful version changes.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

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

@@ -13,11 +13,11 @@ jobs:
       packages: write
     steps:
       - name: Checkout repository
-        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
 
       - name: Docker meta
         id: meta
-        uses: docker/metadata-action@c299e40c65443455700f0fdfc63efafe5b349051 # v5
+        uses: docker/metadata-action@c299e40c65443455700f0fdfc63efafe5b349051 # v5.10.0
         with:
           # list of Docker images to use as base name for tags
           images: |
@@ -34,18 +34,18 @@ jobs:
             type=raw,value=latest,enable={{is_default_branch}}
 
       - name: Set up Docker Buildx
-        uses: docker/setup-buildx-action@8d2750c68a42422c14e847fe6c8ac0403b4cbd6f # v3
+        uses: docker/setup-buildx-action@8d2750c68a42422c14e847fe6c8ac0403b4cbd6f # v3.12.0
 
       - name: Log in to GitHub Container Registry
         if: github.event_name != 'pull_request'
-        uses: docker/login-action@5e57cd118135c172c3672efd75eb46360885c0ef # v3
+        uses: docker/login-action@5e57cd118135c172c3672efd75eb46360885c0ef # v3.6.0
         with:
           registry: ghcr.io
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Build and push Docker image
-        uses: docker/build-push-action@263435318d21b8e681c14492fe198d362a7d2c83 # v6
+        uses: docker/build-push-action@263435318d21b8e681c14492fe198d362a7d2c83 # v6.18.0
         with:
           push: ${{ github.event_name != 'pull_request' }}
           tags: ${{ steps.meta.outputs.tags }}