feat: add configuration management UI for fees, pairings, and application settings

src/arbitrade/storage/repositories.py

@@ -590,6 +590,21 @@ class ConfigSettingRepository:
                 for row in cursor.fetchall()
             ]
 
+    def get_latest_updated_at(self) -> datetime | None:
+        """Get the latest updated_at timestamp from config_settings table."""
+        with self._store.connect() as conn:
+            cursor = conn.execute(
+                """
+                SELECT MAX(updated_at) as latest_updated_at
+                FROM config_settings
+                """
+            )
+            row = cursor.fetchone()
+            if row and row[0]:
+                # Convert string timestamp to datetime
+                return datetime.fromisoformat(row[0].replace('Z', '+00:00'))
+            return None
+
 
 class ConfigPairingRepository:
     def __init__(self, store: DuckDBStore) -> None: