[Overview] Offline support

[marcoambrosini]

• Allow to store data of multiple collectives in pinia at the same time (enh(store): store pages, shares and templates for all collectives #1797)
• Cache app in a service worker (Enh/vite pwa #1977)
• Indicate offline state in UI (feat: track online/offline state #1999, feat(status): Display offline state instead of session list text#7420)
• Persist Text document state in browser with y-indexedDb (enh/y indexeddb text#7621)
• Cleanup stale y-indexedDb databases in browser
• Allow to enter edit mode after browsing to a Collective page with y-indexeddb cache while offline
• Cache Text images in browser (Image Caching text#7318)
• Support to create new page while offline
• Support to set/change page emoji while offline
• Support to rename + delete pages while offline (?)
• Support to tag pages while offline
• Full offline-mode for a collective: sync all pages to y-indexedDb and update regularly without having to open