v4.2.0

Taskwarrior Nautical 4.2.0 is a maintenance and polish release focused on architecture maturity, queue/drain
performance, and a smoother on-exit experience.

Highlights:

• on-exit now has the same explicit runtime/state ownership model as on-modify
• major queue/drain performance work reduced repeated Taskwarrior exports during on-exit
• on-exit can now show a Rich progress bar while draining queued spawns - check the new toggle in the configuration file.

What’s improved:

• added exit_runtime.py so on-exit now uses runtime-owned state and runtime-derived service builders
• reduced on-exit export churn with batch UUID preloading and batch equivalent-child slot preloading
• improved diagnostic output with clearer pretty-printed stats and startup timing blocks
• added exit_progress = true config support for a transient TTY-only drain progress bar on stderr
• refined the progress display with phase and compact counters (ok, skip, rq, dead)
• declared explicit package facade exports in nautical_core/__init__.py
• simplified bootstrap duplication by making the repo-root hook_bootstrap.py a thin shim over the packaged
  implementation
• polished runtime module facades with explicit exports and consistent structure