feat(config): make ArcGIS data source URLs configurable

- Add ARCGIS_CABLE_URL, ARCGIS_LANDING_POINT_URL, ARCGIS_CABLE_LANDING_RELATION_URL to config
- Use @property to read URL from settings in collectors
- URLs can now be configured via environment variables

backend/app/services/collectors/arcgis_relation.py

@@ -1,7 +1,9 @@
 from typing import Dict, Any, List
 from datetime import datetime
+import httpx
 
 from app.services.collectors.base import BaseCollector
+from app.core.config import settings
 
 
 class ArcGISCableLandingRelationCollector(BaseCollector):
@@ -11,11 +13,11 @@ class ArcGISCableLandingRelationCollector(BaseCollector):
     frequency_hours = 168
     data_type = "cable_landing_relation"
 
-    base_url = "https://services.arcgis.com/6DIQcwlPy8knb6sg/arcgis/rest/services/SubmarineCables/FeatureServer/3/query"
+    @property
+    def base_url(self) -> str:
+        return settings.ARCGIS_CABLE_LANDING_RELATION_URL
 
     async def fetch(self) -> List[Dict[str, Any]]:
-        import httpx
-
         params = {"where": "1=1", "outFields": "*", "returnGeometry": "true", "f": "geojson"}
 
         async with httpx.AsyncClient(timeout=60.0) as client: