v0.1.1-beta

• Fix UnboundLocalError for time in on_data_ready (waterfall freeze)
• Move savez_compressed to background thread (unblock GUI on save)
• Save in-progress recording on closeEvent
• Rate-limit buzzer thread to prevent crash after long runs
• Add audio stream watchdog with auto-restart
• Persist all settings, band region, calibration, and spectrum view state
• Alarm auto-recording with timestamp filenames
• Add build_all.bat with isolated venv for PyInstaller packaging

Co-Authored-By: Claude Sonnet 4.6 noreply@anthropic.com