Stale timer bodies were re-delivered to the orchestrator pane after
the parent had already processed the sub-agent's reply and called
close_process. The timer registry held no link to the child
lifecycle, so timers owned by or watching the closed child lingered
until something triggered a fire — e.g. a trailing classifier tick
for the now-removed child.
Add an OnChildClosed hook to ChildEventListener, emit it from
Session.Close (and the terminal-corpse path in reapChild), and have
the timer manager prune the registry: cancel timers owned by the
closed child; remove the closed child from each timer's watched
list (cancel the timer outright when watched empties).
Natural exit deliberately does not route through this hook — the
classifier already emits an idle transition on exit which delivers
any legitimate "fire when sub-agent finishes" semantics exactly
once; cancelling on exit would swallow that.
- Add --debug[=DIR] / --profile[=DIR] flags that write run artefacts
(patterm.log, events.jsonl, per-child raw PTY captures, CPU + heap
+ goroutine pprof) to a dir without polluting stdout/stderr.
- Strengthen vendor-TUI orientation in three places (MCP
initialize.instructions, the spawn_agent tool description, and
help('spawning')) to head off codex's habits of poking the Unix
socket via perl and shelling out to launch peers — both bypass
caller identity and produce orphaned top-level tabs.
- Fix click-and-drag text selection from alt-screen TUIs. Host SGR
mouse reporting now follows the focused child's screen side
instead of being permanently armed; alt-screen TUIs that need
mouse re-enable it themselves and the toggle is forwarded.
- Move drawSidebar() off the per-PTY-chunk hot path. Long claude
session resume was paying a full sidebar rebuild for every
scrolled chunk; the chrome ticker now drains a dirty flag at 60 Hz.
- Gate the per-chunk Title() CGO poll on a containsOSC scan so
codex/ratatui's many SGR-only chunks no longer pay a CGO call each.
