feat(runtime): sync experience bus and learner stack into main

services/memory-service/app/database.py

@@ -443,6 +443,9 @@ class Database:
     ) -> Dict[str, Any]:
         """Create or update a user fact (isolated by agent_id)"""
         import json
+        # Normalize NULL to empty string so ON CONFLICT matches (PostgreSQL: NULL != NULL in unique)
+        _agent_id = (agent_id or "").strip()
+        _team_id = team_id or ""
         # Convert dict to JSON string for asyncpg JSONB
         json_value = json.dumps(fact_value_json) if fact_value_json else None
         
@@ -457,7 +460,7 @@ class Database:
                         fact_value_json = EXCLUDED.fact_value_json,
                         updated_at = NOW()
                     RETURNING *
-                """, user_id, team_id, agent_id, fact_key, fact_value, json_value)
+                """, user_id, _team_id, _agent_id, fact_key, fact_value, json_value)
             except asyncpg.exceptions.InvalidColumnReferenceError:
                 # Backward compatibility for DBs that only have UNIQUE(user_id, team_id, fact_key).
                 row = await conn.fetchrow("""
@@ -470,7 +473,7 @@ class Database:
                         fact_value_json = EXCLUDED.fact_value_json,
                         updated_at = NOW()
                     RETURNING *
-                """, user_id, team_id, agent_id, fact_key, fact_value, json_value)
+                """, user_id, _team_id, _agent_id, fact_key, fact_value, json_value)
             
         return dict(row) if row else {}