feat: Add EspoCRM and Advoware integration for Beteiligte comparison

- Implemented `compare_beteiligte.py` script for comparing Beteiligte structures between EspoCRM and Advoware.
- Created `beteiligte_comparison_result.json` to store comparison results.
- Developed `EspoCRMAPI` service for handling API interactions with EspoCRM.
- Added comprehensive documentation for the EspoCRM API service.
- Included error handling and logging for API operations.
- Enhanced entity management with CRUD operations and search capabilities.

bitbylaw/services/advoware.py

@@ -122,7 +122,9 @@ class AdvowareAPI:
                        params: Optional[Dict] = None, json_data: Optional[Dict] = None,
                        files: Optional[Any] = None, data: Optional[Any] = None,
                        timeout_seconds: Optional[int] = None) -> Any:
-        url = self.API_BASE_URL + endpoint
+        # Bereinige doppelte Slashes
+        endpoint = endpoint.lstrip('/')
+        url = self.API_BASE_URL.rstrip('/') + '/' + endpoint
         effective_timeout = aiohttp.ClientTimeout(total=timeout_seconds or Config.ADVOWARE_API_TIMEOUT_SECONDS)
         token = self.get_access_token()  # Sync call
         effective_headers = headers.copy() if headers else {}