Add better jail configuration: file CRUD, enable/disable, log paths

Task 4 (Better Jail Configuration) implementation:
- Add fail2ban_config_dir setting to app/config.py
- New file_config_service: list/view/edit/create jail.d, filter.d, action.d files
  with path-traversal prevention and 512 KB content size limit
- New file_config router: GET/PUT/POST endpoints for jail files, filter files,
  and action files; PUT .../enabled for toggle on/off
- Extend config_service with delete_log_path() and add_log_path()
- Add DELETE /api/config/jails/{name}/logpath and POST /api/config/jails/{name}/logpath
- Extend geo router with re-resolve endpoint; add geo_re_resolve background task
- Update blocklist_service with revised scheduling helpers
- Update Docker compose files with BANGUI_FAIL2BAN_CONFIG_DIR env var and
  rw volume mount for the fail2ban config directory
- Frontend: new Jail Files, Filters, Actions tabs in ConfigPage; file editor
  with accordion-per-file, editable textarea, save/create; add/delete log paths
- Frontend: types in types/config.ts; API calls in api/config.ts and api/endpoints.ts
- 63 new backend tests (test_file_config_service, test_file_config, test_geo_re_resolve)
- 6 new frontend tests in ConfigPageLogPath.test.tsx
- ruff, mypy --strict, tsc --noEmit, eslint: all clean; 617 backend tests pass

backend/app/models/geo.py

@@ -32,6 +32,21 @@ class GeoDetail(BaseModel):
     )
 
 
+class GeoCacheStatsResponse(BaseModel):
+    """Response for ``GET /api/geo/stats``.
+
+    Exposes diagnostic counters of the geo cache subsystem so operators
+    can assess resolution health from the UI or CLI.
+    """
+
+    model_config = ConfigDict(strict=True)
+
+    cache_size: int = Field(..., description="Number of positive entries in the in-memory cache.")
+    unresolved: int = Field(..., description="Number of geo_cache rows with country_code IS NULL.")
+    neg_cache_size: int = Field(..., description="Number of entries in the in-memory negative cache.")
+    dirty_size: int = Field(..., description="Number of newly resolved entries not yet flushed to disk.")
+
+
 class IpLookupResponse(BaseModel):
     """Response for ``GET /api/geo/lookup/{ip}``.