Refactor geocoding services and improve logging

- Updated the Nominatim geocoding service to use a class-based structure and accept a logger instance for better logging control.
- Modified tests for the Nominatim service to align with the new structure and improved logging assertions.
- Removed the disabled notification service test file.
- Added a new GeocodingFailedError class to handle geocoding failures more explicitly.
- Enhanced error logging in the queue service to include structured error objects.
- Updated user service to accept a logger instance for better logging in address upsert operations.
- Added request-scoped logger to Express Request interface for type-safe logging in route handlers.
- Improved logging in utility functions for better debugging and error tracking.
- Created a new GoogleGeocodingService class for Google Maps geocoding with structured logging.
- Added tests for the useAiAnalysis hook to ensure proper functionality and error handling.

express.d.ts

@@ -0,0 +1,15 @@
+// src/types/express.d.ts
+import { Logger } from 'pino';
+
+/**
+ * This file uses declaration merging to add a custom `log` property to the
+ * global Express Request interface. This makes the request-scoped logger
+ * available in a type-safe way in all route handlers, as required by ADR-004.
+ */
+declare global {
+  namespace Express {
+    export interface Request {
+      log: Logger;
+    }
+  }
+}