feat: branch/PR naming standard CI check

Composite action that validates head branch and PR title against the
fritzlab naming standard (role/bug-id/kebab + [bug-id] titles).
Always exits 0 (warn-only) until the Bugs system is live.

- check.sh: validation logic (branch form, title form, bug-id cross-check)
- action.yaml: composite action wrapping check.sh
- tests/run: 20-case test matrix (valid/invalid/chore/mismatch/dfritz)
- .gitea/workflows/test.yaml: CI that runs the test suite

Closes fritzlab/agenthub#559

.gitea/workflows/test.yaml

@@ -0,0 +1,13 @@
+name: test
+on:
+  push:
+    branches: [main]
+  pull_request:
+jobs:
+  test:
+    runs-on: fritzlab
+    timeout-minutes: 5
+    steps:
+      - uses: actions/checkout@v4
+      - name: run tests
+        run: bash tests/run