- Extract milestoneColor to utils/palette.ts; remove duplicate in HomeView + ProjectListView
- Create useBackgroundRefresh composable; wire into HomeView + BriefingView (removes manual setInterval/clearInterval boilerplate)
- Extract _loadTabContent() in SettingsView so watch and onMounted share one tab→loader mapping
- Move raw fetch() api-key calls to typed helpers in api/client.ts (listApiKeys, createApiKey, revokeApiKey)
- Drop unused onUnmounted import from BriefingView
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
