choredocker): enhance local Docker socket access and error handling

- Added guidance for Docker socket group access in docker-compose files.
- Introduced docker-compose.override.example.yml for supplemental group configuration.
- Improved entrypoint diagnostics to include socket GID and group guidance.
- Updated README with instructions for setting up Docker socket access.
- Enhanced backend error handling to provide actionable messages for permission issues.
- Updated frontend components to display troubleshooting information regarding Docker socket access.
- Added tests to ensure proper error messages and guidance are rendered in UI.
- Revised code coverage settings to include Docker service files for better regression tracking.

.docker/compose/docker-compose.dev.yml

@@ -32,6 +32,8 @@ services:
       #- CPM_SECURITY_RATELIMIT_ENABLED=false
       #- CPM_SECURITY_ACL_ENABLED=false
       - FEATURE_CERBERUS_ENABLED=true
+    # Docker socket group access: copy docker-compose.override.example.yml
+    # to docker-compose.override.yml and set your host's docker GID.
     volumes:
       - /var/run/docker.sock:/var/run/docker.sock:ro # For local container discovery
       - crowdsec_data:/app/data/crowdsec