feat(ci): add automatic PR labeling workflow (#473)

Configure actions/labeler@v5 to automatically label PRs based on file paths.
Maps changes to: app, web, documentation, ci, tests, installer, resources, dependencies.

Creates 6 new labels to complement existing issue labels for better PR organization.

.github/workflows/labeler.yml

@@ -0,0 +1,18 @@
+name: "Pull Request Labeler"
+
+on:
+  pull_request_target:
+    types: [opened, synchronize, reopened]
+
+jobs:
+  labeler:
+    permissions:
+      contents: read
+      pull-requests: write
+    runs-on: ubuntu-latest
+    steps:
+      - name: Label PR
+        uses: actions/labeler@v5
+        with:
+          repo-token: "${{ secrets.GITHUB_TOKEN }}"
+          sync-labels: true