chore(release): prepare v0.14.0-beta

* chore(release): prepare v0.14.0-beta

- Bump version 0.13.0-beta -> 0.14.0-beta (src/vocalinux/version.py)
- README: refresh What's New for v0.14.0-beta and bump comparison table
- docs/UPDATE.md: add v0.14.0-beta section and bump checkout example
- SECURITY.md: mark 0.14.x supported, 0.13.x unsupported
- docs/RELEASE_PROCESS.md: add v0.14.0-beta to version history
- web: bump package.json / package-lock.json / page.tsx schema + badge
- web changelog: add v0.14.0-beta entry

* ci(codecov): allow 0.5% project coverage threshold

Prevents version-bump/docs-only PRs from being blocked by minor
coverage fluctuations (e.g. -0.04% on a release-prep branch).

* docs(release): correct chronological order in version history table

* docs(release): add #509 shortcut UI exclusivity fix to v0.14.0-beta notes

docs/RELEASE_PROCESS.md

@@ -344,6 +344,7 @@ git push origin v0.5.1-beta
 | 0.11.0-beta | 2026-05-30 | Beta | Advanced Settings tab, IBus/recognition hardening, installer fixes, distro compatibility |
 | 0.12.0-beta | 2026-06-07 | Beta | Remote API engine, Silero VAD, threading/IBus hardening, settings and installer fixes |
 | 0.13.0-beta | 2026-06-30 | Beta | Guided whisper.cpp model variants, Wayland text-injection reliability, hotplug keyboard support, dictation spacing fix, website docs refresh |
+| 0.14.0-beta | 2026-07-13 | Beta | Configurable modifier+key hotkeys, FunASR/SenseVoice remote-API support, GNOME/KDE Wayland IBus reliability fixes, audio crash fix, hybrid-CPU efficiency fix |
 
 ## Questions?