Single port (TTS_PORT) handles both the WS upgrade handshake and
connections. Adds job queue, generation worker, playback events
(queued/started/finished/aborted/error), and abort_current/abort_all
commands. Fixes BrokenPipeError when pacat is killed mid-write.
Updates all examples to use WebSocket; adds abort-demo.mjs.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
