fix(mcp): broaden pre-call session cleanup to catch DBAPIError not just OperationalError

Some database drivers (e.g. MySQL, SQLite) surface dropped connections as
InterfaceError rather than OperationalError. Both are DBAPIError subclasses.
Widen the catch in _remove_session_safe() so all DBAPI-level disconnect
errors are handled consistently regardless of driver.

superset/mcp_service/auth.py

@@ -523,7 +523,9 @@ def _remove_session_safe() -> None:
     the session is removed to prevent a prior request's thread-local session
     from leaking into the next one.  If the underlying DBAPI connection died
     between requests (e.g. RDS SSL idle-timeout or max-connection-age), the
-    rollback implicit in ``session.close()`` raises ``OperationalError``.
+    rollback implicit in ``session.close()`` raises a ``DBAPIError`` subclass
+    (``OperationalError`` for psycopg2, ``InterfaceError`` for some other
+    drivers).
 
     When that happens:
     1. Invalidate the dead connection so the pool discards it (rather than
@@ -533,13 +535,13 @@ def _remove_session_safe() -> None:
     The tool call still proceeds because a fresh connection will be obtained
     on the next DB access.
     """
-    from sqlalchemy.exc import OperationalError
+    from sqlalchemy.exc import DBAPIError
 
     from superset.extensions import db
 
     try:
         db.session.remove()
-    except OperationalError as exc:
+    except DBAPIError as exc:
         logger.warning(
             "Connection error during pre-call session cleanup "
             "(likely SSL/idle timeout); invalidating connection and retrying: %s",