Recommendations & phases

Phase 1: Core completeness (1–2 weeks)

1. Add file attachment upload to compose
2. Add calendar event edit/delete
3. Implement toast notification system
4. Add undo toast for archive/delete/move
5. Add next/prev navigation in thread view
6. Wire bulk action toolbar to existing API

Phase 2: Productivity features (2–4 weeks)

1. Keyboard shortcuts (j/k navigation, e/r/a actions)
2. Recipient autocomplete with recent addresses
3. Draft autosave with JS debounce
4. Day/month calendar views
5. Multi-select checkboxes in email list

Phase 3: Polish & power features (4–8 weeks)

1. Rich text editor (Tiptap/Quill)
2. Mobile responsive overhaul
3. Snooze functionality
4. Email filters/rules UI
5. Contacts browser
6. Dark mode theme