mu 3.10.2

The TUI exits on q again with sync on. Upgrade with
npm i -g @mu-crew/mu@3.10.2. No schema or pi extension change.

Fixed

• mu hung after q when MU_SYNC_DIR was set. The TUI stopped
  rendering but the process never exited: the 3.10.0 sync worker was
  unref'd before its message listener was attached, and attaching it
  re-refs the worker. It is now unref'd after its listeners.
• The TUI's exit flush no longer waits for the segment lock. After
  q, the flush could wait up to 2 s on a lock held by another mu
  process. The TUI (bare mu, mu state --tui) now tries the lock
  once; if it is busy, nothing is written and the ops stay in the DB
  for the next flush. The TUI's worker has already flushed every 10 s.
  Other verbs keep the 2 s wait. Exit is ~150-450 ms when the segment
  manifest is sealed. A mu older than 3.10.0 still running on this
  machine rewrites it unsealed, which makes every flush rescan the
  segment, so restart those processes.