feat: add bgp observability and admin ui improvements

backend/app/models/collected_data.py

@@ -4,6 +4,7 @@ from sqlalchemy import Boolean, Column, DateTime, ForeignKey, Integer, String, T
 from sqlalchemy.sql import func
 
 from app.core.collected_data_fields import get_record_field
+from app.core.time import to_iso8601_utc
 from app.db.session import Base
 
 
@@ -74,15 +75,11 @@ class CollectedData(Base):
             "value": get_record_field(self, "value"),
             "unit": get_record_field(self, "unit"),
             "metadata": self.extra_data,
-            "collected_at": self.collected_at.isoformat()
-            if self.collected_at is not None
-            else None,
-            "reference_date": self.reference_date.isoformat()
-            if self.reference_date is not None
-            else None,
+            "collected_at": to_iso8601_utc(self.collected_at),
+            "reference_date": to_iso8601_utc(self.reference_date),
             "is_current": self.is_current,
             "previous_record_id": self.previous_record_id,
             "change_type": self.change_type,
             "change_summary": self.change_summary,
-            "deleted_at": self.deleted_at.isoformat() if self.deleted_at is not None else None,
+            "deleted_at": to_iso8601_utc(self.deleted_at),
         }