fix: IMAP full sync via UID SEARCH+FETCH; add sync log UI

- Replace full-sync fetchMessages(1:*) with UID SEARCH ALL + UID FETCH
  so every message gets a reliable UID on all servers
- Guard CONDSTORE select on server capability to avoid BAD from
  servers that do not advertise CONDSTORE/QRESYNC
- Add SyncLogEntry model + observeSyncLogs stream to SyncLogRepository
- Add SyncLogScreen with per-entry duration/error display
- Wire history icon in SettingsScreen → /accounts/:id/sync-log route
- Fix FakeImapClient to expose initialized serverInfo via field override

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

LATER.md

@@ -1,11 +1,29 @@
 # Later
 
+done?
+
 think about that: Maybe we should not mock jmap/imap/smtp. We  have a temproary Stalwart.
 
 Just like mocking DB in Django makes no sense.
 
 ---
 
+Try Qwen, vscode plugin
+
+---
+
+test/unit/fake_imap.dart
+
+Why is that still needed? We have Stalwart.
+
+---
+
+du -a | sort -rn | head
+
+Why is the directory so big? 4 GByte?
+
+---
+
 After Try Connection, show some matching icon next to the text.
 
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