0.9.4 — stability & UX fix batch

- hive-client: composer/sidebar selection fixes, exception-safe UI jobs, first unit tests, UiApi select-agent hook
- routine orphan self-heal (thread delete → rebind, scheduler no longer disables on error)
- thread-etiquette system prompt (cross-agent noise + ack-storms)
- browser freeze fixes: zombie-aware x11vnc watchdog, idle watcher respects busy agents, pkill  fixes
- workspace read-only flip fixed: screen recreate now passes --userns=keep-id
- deploy skill v1.3.0