docs: Update outdated GitHub Actions versions

.github/workflows/docker-publish.yml

@@ -19,10 +19,10 @@ jobs:
       DATABASE_URL: "postgresql://test:test@localhost:5432/test"
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Setup Node.js
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
           node-version: '24'
           cache: 'npm'
@@ -42,7 +42,7 @@ jobs:
 
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
 
       - name: Set up Docker Buildx
         uses: docker/setup-buildx-action@v3
@@ -66,7 +66,7 @@ jobs:
             type=raw,value=latest,enable={{is_default_branch}}
 
       - name: Build and push Docker image
-        uses: docker/build-push-action@v5
+        uses: docker/build-push-action@v6
         with:
           context: .
           file: ./docker/Dockerfile

.github/workflows/update-contributors.yml

@@ -11,13 +11,13 @@ jobs:
     
     steps:
       - name: Checkout repository
-        uses: actions/checkout@v4
+        uses: actions/checkout@v6
         with:
           fetch-depth: 0 # Full history needed for commit deduplication
           token: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Set up Python
-        uses: actions/setup-python@v5
+        uses: actions/setup-python@v6
         with:
           python-version: '3.x'