* fix(suspend): delay keyboard restart to 6s for USB re-enumeration
The 2s delay is enough for the speech engine, but USB devices
re-enumerate slowly after resume. At T+2s, stale /dev/input nodes
still exist and evdev opens them, but the kernel tears them down
at ~T+4s, causing another round of disconnections.
Split the reinit into two separate timers:
- 2s: speech engine reinit (unchanged)
- 6s: keyboard backend restart (after USB re-enumeration completes)
* fix(suspend): use inotify to detect device settle before keyboard restart
Replace hard-coded 6s keyboard restart delay with event-driven
Gio.File.monitor_directory() on /dev/input. After resume, a 2s settle
timer resets on each inotify event; keyboard shortcuts restart only once
devices stop changing. A 10s safety cap and a 6s fallback timer guard
against environments where inotify is unavailable.
