032: fix async chain for target schema check + mapper + executor

resolve_database_id → async (was sync but called async SupersetClient methods)
  - await client.get_database(db_id)
  - await client.get_databases(...)

validate_target_table_schema → async (calls async resolve_database_id + execute_and_poll)
  - await executor.resolve_database_id(...)
  - await executor.execute_and_poll(...)

Route check_target_schema → await validate_target_table_schema(...)

MapperPlugin.execute → await executor.resolve_database_id(...)
  (execute() was already async def, just missing await)

SupersetSqlLabExecutor.execute_sql → await self.resolve_database_id()
  (was sync call to now-async method)

backend/src/api/routes/translate/_job_routes.py

@@ -269,7 +269,7 @@ async def check_target_schema(
         extra={"src": "translate_routes"},
     )
     try:
-        result = validate_target_table_schema(payload, config_manager)
+        result = await validate_target_table_schema(payload, config_manager)
         return result
     except Exception as e:
         logger.explore("check_target_schema failed",

backend/src/plugins/mapper.py

@@ -167,7 +167,7 @@ class MapperPlugin(PluginBase):
                     if not database_id:
                         log.error("database_id is required for sqllab source.")
                         raise ValueError("database_id is required for sqllab source.")
-                    executor.resolve_database_id(target_database_id=str(database_id))
+                    await executor.resolve_database_id(target_database_id=str(database_id))
 
                     mapper.run_mapping(
                         superset_client=client,

backend/src/plugins/translate/service_target_schema.py

@@ -189,7 +189,7 @@ def _parse_sqllab_result(result: dict[str, Any]) -> tuple[list[dict[str, Any]],
 # @RELATION DEPENDS_ON -> [_extract_columns_from_rows]
 # @RELATION DEPENDS_ON -> [_parse_sqllab_result]
 # @RELATION DEPENDS_ON -> [SupersetSqlLabExecutor]
-def validate_target_table_schema(
+async def validate_target_table_schema(
     req: TargetSchemaValidationRequest,
     config_manager: ConfigManager,
 ) -> TargetSchemaValidationResponse:
@@ -238,7 +238,7 @@ def validate_target_table_schema(
 
         try:
             executor = SupersetSqlLabExecutor(config_manager, req.environment_id)
-            executor.resolve_database_id(target_database_id=req.target_database_id)
+            await executor.resolve_database_id(target_database_id=req.target_database_id)
             backend = executor.get_database_backend() or ""
             db_name = executor.get_database_name() or "unknown"
 
@@ -290,7 +290,7 @@ def validate_target_table_schema(
             logger.reason("Executing SQL Lab query",
                           extra={"payload": {"sql": sql[:200], "backend": backend, "database_name": db_name}})
 
-            result = executor.execute_and_poll(sql=sql, max_polls=15, poll_interval_seconds=1.0)
+            result = await executor.execute_and_poll(sql=sql, max_polls=15, poll_interval_seconds=1.0)
             status = result.get("status", "")
 
             if status == "failed":

backend/src/plugins/translate/superset_executor.py

@@ -58,7 +58,7 @@ class SupersetSqlLabExecutor:
     # @PRE database_name or database_id should be known.
     # @POST Returns database_id integer or raises ValueError. Also sets self._database_backend.
     # @SIDE_EFFECT Fetches databases list from Superset; optionally fetches single DB for backend.
-    def resolve_database_id(
+    async def resolve_database_id(
         self,
         database_name: str | None = None,
         target_database_id: str | None = None,
@@ -71,7 +71,7 @@ class SupersetSqlLabExecutor:
                 try:
                     db_id = int(target_database_id)
                     # Fetch full DB info to get backend
-                    db_info = client.get_database(db_id)
+                    db_info = await client.get_database(db_id)
                     result = db_info.get("result", db_info)
                     self._database_id = result.get("id", db_id)
                     self._database_backend = result.get("backend") or result.get("engine")
@@ -92,7 +92,7 @@ class SupersetSqlLabExecutor:
                     # Fall through to default resolution
 
             # Fetch full database list with backend info
-            _, databases = client.get_databases(
+            _, databases = await client.get_databases(
                 query={"columns": ["id", "database_name", "backend"]}
             )
             if not databases:
@@ -156,7 +156,7 @@ class SupersetSqlLabExecutor:
             client = self._get_client()
             db_id = database_id or self._database_id
             if not db_id:
-                db_id = self.resolve_database_id()
+                db_id = await self.resolve_database_id()
 
             logger.reason("Submitting SQL to Superset SQL Lab", {
                 "database_id": db_id,