When the MCP server runs over stdio transport, stdin/stdout are closed
before the call_on_close promo callback fires. sys.stdin.isatty() then
raises ValueError: I/O operation on closed file.
Wrap the isatty() calls in a try/except ValueError in
_is_interactive_session() so the promo is silently skipped rather than
crashing the shutdown path.
Fixes#607
Co-authored-by: bm-clawd <bm-clawd@users.noreply.github.com>
Signed-off-by: claude[bot] <41898282+claude[bot]@users.noreply.github.com>
claude[bot]
e5a1f7e683