feat: add data sources config system and Earth API integration

- Add data_sources.yaml for configurable data source URLs
- Add data_sources.py to load config with database override support
- Add arcgis_landing_points and arcgis_cable_landing_relation collectors
- Change visualization API to query arcgis_landing_points
- Add /api/v1/datasources/configs/all endpoint
- Update Earth to fetch from API instead of static files
- Fix scheduler collector ID mappings

backend/app/core/data_sources.py

@@ -0,0 +1,78 @@
+import os
+import yaml
+from functools import lru_cache
+from typing import Optional
+
+
+COLLECTOR_URL_KEYS = {
+    "arcgis_cables": "arcgis.cable_url",
+    "arcgis_landing_points": "arcgis.landing_point_url",
+    "arcgis_cable_landing_relation": "arcgis.cable_landing_relation_url",
+    "fao_landing_points": "fao.landing_point_url",
+    "telegeography_cables": "telegeography.cable_url",
+    "telegeography_landing": "telegeography.landing_point_url",
+    "huggingface_models": "huggingface.models_url",
+    "huggingface_datasets": "huggingface.datasets_url",
+    "huggingface_spaces": "huggingface.spaces_url",
+    "cloudflare_radar_device": "cloudflare.radar_device_url",
+    "cloudflare_radar_traffic": "cloudflare.radar_traffic_url",
+    "cloudflare_radar_top_locations": "cloudflare.radar_top_locations_url",
+    "peeringdb_ixp": "peeringdb.ixp_url",
+    "peeringdb_network": "peeringdb.network_url",
+    "peeringdb_facility": "peeringdb.facility_url",
+    "top500": "top500.url",
+    "epoch_ai_gpu": "epoch_ai.gpu_clusters_url",
+}
+
+
+class DataSourcesConfig:
+    def __init__(self, config_path: str = None):
+        if config_path is None:
+            config_path = os.path.join(os.path.dirname(__file__), "data_sources.yaml")
+
+        self._yaml_config = {}
+        if os.path.exists(config_path):
+            with open(config_path, "r") as f:
+                self._yaml_config = yaml.safe_load(f) or {}
+
+    def get_yaml_url(self, collector_name: str) -> str:
+        key = COLLECTOR_URL_KEYS.get(collector_name, "")
+        if not key:
+            return ""
+
+        parts = key.split(".")
+        value = self._yaml_config
+        for part in parts:
+            if isinstance(value, dict):
+                value = value.get(part, "")
+            else:
+                return ""
+        return value if isinstance(value, str) else ""
+
+    async def get_url(self, collector_name: str, db) -> str:
+        yaml_url = self.get_yaml_url(collector_name)
+
+        if not db:
+            return yaml_url
+
+        try:
+            from sqlalchemy import select
+            from app.models.datasource_config import DataSourceConfig
+
+            query = select(DataSourceConfig).where(
+                DataSourceConfig.name == collector_name, DataSourceConfig.is_active == True
+            )
+            result = await db.execute(query)
+            db_config = result.scalar_one_or_none()
+
+            if db_config and db_config.endpoint:
+                return db_config.endpoint
+        except Exception:
+            pass
+
+        return yaml_url
+
+
+@lru_cache()
+def get_data_sources_config() -> DataSourcesConfig:
+    return DataSourcesConfig()