Adds markAllAsRead(accountId, mailboxPath) to EmailRepository — bulk
marks all unread emails as seen (optimistic local update + pending
change per email for server sync). A PopupMenuButton in EmailListScreen
exposes this as 'Mark all as read'. Contract test verifies the mailbox-
scoped behaviour.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
- Add snoozedUntil and snoozedFromMailboxPath to Emails table.
- Implement snoozeEmail and wakeUpEmails in EmailRepository.
- Update IMAP and JMAP flush logic to handle snooze/unsnooze.
- Update sync logic to parse snz: keywords from server.
- Add SnoozePicker widget and integrate into UI.
- Add unit tests for Snooze logic.
