feat: add auto language detection, fix tab duplication and login state}
- Add "Auto (system)" language option that detects OS locale and maps it to the nearest supported translation, available in Settings menu - Default to auto language detection on first run instead of English - Expose detectOsLocale function in registry for menu language switching - Fix tab duplication to preserve the original tab's partition and account - Stagger loading of tabs sharing the same partition to avoid session conflicts (defer until first shared-partition tab fires dom-ready) - Fix auto-launch checkbox by persisting startOnLogin in app config instead of querying OS login-item settings which could return stale state - Suppress "checking-for-update" notification on initial launch - Add 'auto' and 'duplicateTabNotice' translation strings for all 30 locales - Add changelog entries for v2026.4.126 and v2026.4.127 - Bump version to v2026.4.129 - Clean up template literal formatting and remove stale console.log in menu