Manual port of apache/superset#39917 (commit 85935b0b) onto 6.0-release.
A clean cherry-pick does not apply because mcp_service/auth.py has diverged
structurally on this branch, but the vulnerable code path is present verbatim:
sync_wrapper calls db.session.remove() before user resolution on reused
thread-pool threads. If the thread-local DBAPI connection died between
requests (RDS SSL idle-timeout / max-connection-age), the implicit rollback
raises a DBAPIError and crashes the tool call.
Wrap the pre-call remove in _remove_session_safe(), which catches DBAPIError,
invalidates the dead connection so the pool discards it, and retries remove()
so the tool proceeds on a fresh connection. Ports the accompanying regression
test byte-for-byte behaviorally.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
