Fix CI: add matcher/ to PYTHONPATH for bare 'import database'

matcher.py uses 'import database' (flat Docker layout) so the
matcher/ directory must be on PYTHONPATH alongside the project root.

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

.github/workflows/ci.yml

@@ -29,7 +29,7 @@ jobs:
       - name: Run tests
         run: |
           sudo ln -s $GITHUB_WORKSPACE /app
-          pytest matcher/test_matcher.py -v
+          PYTHONPATH=$GITHUB_WORKSPACE:$GITHUB_WORKSPACE/matcher pytest matcher/test_matcher.py -v
 
   docker-build:
     name: Docker Build Check