fix(tui): v2+v3 bug fixes, pending input queue, ! shell magic, /resume

[shenhao-stu]

Summary

Bundle of v2/v3 TUI bug fixes + two new features (pending-input queue, ! shell magic) + /resume wiring + cherry-picked upstream fixes (#466, #461).

Bug fixes

• v2 Ctrl+S freeze on long sessions — Defers reset() + cleanup via call_after_refresh. _skip_change_next short-circuits the synchronous Changed event so the keystroke handler returns instantly even when streaming saturates the reactive queue.
• v3 terminal title only "GenericAgent" — Route _set_term_title via os.write(1, ...); PTK redirects sys.stdout to sb_agent.log, so the OSC 0 escape was landing in the log instead of the terminal. Default session name = \"session\" for v2 parity; repaint on running→idle.
• v3 user input bg cutoff — _tile() now pads explicit bg-active spaces to width. PTK's cell renderer doesn't honour \x1b[K, so the charcoal user-bubble band used to stop at text length.
• v3 ask_user freeze on "请你coderun以下" — _tool_status no longer marks an in-flight ask_user chip as ✓ ok while the stream still contains Waiting for your answer .... Bumped DoneEvent grace to 10 s when that marker is in the stream so a slow ask_user_queue.put doesn't cause the picker to fall through to _finalize.
• v3 /scheduler can't see running services — Added pre_checked kwarg to _show_menu so the running set lands atomically with the rest of the menu state (PTK could otherwise render the menu before the post-_show_menu override took effect). slash_cmds._match_service relaxed to path-only so directly-launched (python reflect/foo.py) services are detected. Running rows colored functional green in both v2 + v3.
• /scheduler confirm card → left arrow rollback — ChoiceList and v3 _menu_card now treat ← as cancel (parity with Esc) so the user can roll back to the picker one-handed.
• "Turn 1 ..." marker leaking into scrollback — Setting agent.task_dir (required for the _intervene hook below) flips agent_loop.py:52 to emit the short **Turn N ...** form. Extended all four v3 turn-marker regexes (_TURN_MARKER_RE, _TURN_SPLIT_FOLD_RE, _TURN_MK_RE, and the _safe_pos inline patterns) plus the v2 split-pattern to match either form.

New features

• Pending input queue (v2 + v3) — Submit while the agent is running no longer rejects. Queued entries render as [queued #N] markers and live in a preview block above the input. 5 s cooldown that resets per new pending, then drains via <task_dir>/_intervene (mid-turn) — the agent picks up the combined text at the next turn boundary thanks to ga.turn_end_callback. Falls back to put_task when the agent is idle. ↑ recalls the most-recent queued entry for amendment; Esc clears the queue.
• ! shell magic command (v2 + v3) — Prefix ! enters shell mode: pink border, prompt mark swaps to !, body strips the leading ! so the glyph shows once. Enter runs the rest as subprocess.run(shell=True, timeout=30), echoes ! cmd + └ output into scrollback, and appends to the LLM history so a follow-up like "what did I just run?" finds the context. The history append routes through _intervene while the agent is running to avoid racing the runner thread's iteration of backend.history.
• /resume wiring — Forwarded as a literal to the agent so GA's _handle_slash_cmd (agentmain.py:124) can expand it. Added to the v3 palette, v2 COMMANDS, slash_cmds.COMMANDS, i18n (en+zh), /help, and tip rotations.

v3 emoji polish

• Dropped _PETS_ASCII / _PETS_BUNNY / _PETS_BLOB.
• Restored bear calm tier to ʕ•ᴥ•ʔ (default).
• cat + dot calm tiers use •; focused tier uses o — mood progression matches user-requested aesthetic.
• Pet refresh decoupled from spinner via self._spin // 5 so the face cycles at ~0.5 s while the spinner stays snappy at 0.1 s.

v3 keybindings

• Esc Esc (within 800 ms) → /rewind. Handled inside _handle_key because PTK's Esc interception swallows it before _keys runs.

Cherry-picked upstream fixes

• PR fix(tui): prevent crash when /rewind picker triggers session remount #466 (8ae3645) — _collapse_choice early-return when the on_select callback (e.g. /rewind) detaches the anchor widget.
• PR Fix stale SelectableStatic mouse events in TUI #461 (08f21e8) — SelectableStatic.has_valid_selection_parent + app-level _is_stale_selectable_mouse_event filter that swallows mouse events on detached widgets.

Test plan

• v2 Ctrl+S after 100+ messages in a streaming session — input clears within a frame, no freeze
• v3 terminal title shows ⠋ <session> · GenericAgent during run and <session> · GenericAgent at idle
• v3 user message bubble extends its charcoal band to the right edge
• v3 /emoji opens picker; bear default; pet visibly slower than spinner
• v3 input 请你coderun以下 → ask_user chip stays · … until answered; ask card renders inline with input
• /scheduler shows running services pre-checked (green) in both v2 + v3; ← on confirm card rolls back
• No Turn 1 ... text in scrollback during normal runs
• v3 Esc Esc within 800 ms → /rewind picker
• Submit while agent is running → row appears in pending preview; ↑ recalls; Esc clears; 5 s of silence → message lands as [MASTER] ... in the next LLM call's prompt
• !echo hi → scrollback shows ! echo hi / └ hi; agent recalls the command on a follow-up question
• /resume in either TUI lists recent sessions