45c72d874f
The stuck-card pattern: after a Back TR the card re-issues the parent menu
as a new SELECT ITEM (91XX -> FETCH, paused, awaiting TR), but the UI's
back/timeout branch ignored that response and showed the cached top menu;
the next item click then sent ENVELOPE(Menu Selection) while the card was
waiting for the TR. The card answers such an ENVELOPE with 9000 (not the
usual 91XX), and menu-select cleared the pending command without a TR,
leaving an unfinished proactive session until reset/equip.
- server: _finish_pending_menu() answers a paused command with a cancel TR
(0x10) before /api/menu-select sends its ENVELOPE and drains a 91XX
follow-up, so a new selection can never shadow an unanswered FETCH
- frontend: stkMenuRespond('back'|'timeout') renders the follow-up command
from the server response (SELECT ITEM / DISPLAY TEXT) and shows the
cached top menu only when the TR answer carries no command (9000)
- tests: finish-pending cancel TR + chain drain (Python); stkMenuRespond
back/timeout/cancel/ok rendering (frontend); help/AGENTS updated;
SW cache v107 -> v108.