ci: add pr labeller config and workflow

.github/labeler.yml

@@ -0,0 +1,16 @@
+"frontend":
+  - "src/frontend/**/*"
+"backend":
+  - "src/backend/**/*"
+"devops":
+  - ".github/**/*"
+  - "docker-*.yml"
+  - "**/Dockerfile"
+  - "**/*.dockerfile"
+  - "**/*entrypoint.sh"
+"migration":
+  - "src/backend/app/migrations/**/*"
+"docs":
+  - "docs/**/*"
+  - "mkdocs.yml"
+  - "README.md"

.github/workflows/pr_label.yml

@@ -0,0 +1,14 @@
+name: 🏷️ PR Label
+
+on:
+  pull_request_target:
+
+jobs:
+  pr-label:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/labeler@v5
+        # Uses .github/labeler.yml definitions
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}