mail UX: restore-to-folder, draft/attachment fixes, printing, sidebar collapse

Backend:
- Restore returns each message to its original folder (e.g. Sent/Archive) instead
  of always the Inbox: new messages.restore_mailbox_id (migration 0010) +
  restore_thread_job.
- Drafts: expunge reconciliation for the Drafts poll (provider.list_uids /
  _reconcile_drafts) clears phantom "remote" drafts; send + discard drop the
  mirrored DB row; adopting a remote draft carries its real attachments into the
  compose flow.
- Thread detail/list are folder-aware: individually trashed/spam messages are
  hidden outside their folder, Trash/Spam show only their own messages, and the
  mail-list message count matches the view.

Frontend:
- Thread reading panel: fix newest-first card overlap/spacing (expand-all and
  single expand), hide Reply/Forward on trashed messages, close the Actions menu
  on message-body (iframe) clicks, scroll to the inline composer, and prompt
  Save draft / Discard on the X close.
- Composer: remount when switching drafts, dirty-tracking to stop duplicate IMAP
  mirrors, and close the From/More dropdowns on outside click.
- Sidebar: collapse/expand toggle (icons-only ~60px rail) and a log-out icon on
  Sign out.
- Mail-standard printing in a new window with reliable page margins (lib/print.ts).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01U72FZiF1W1pb8XxyWBTREA

backend/workers/worker.py

@@ -19,6 +19,7 @@ from app.sync.actions import (
     move_job,
     move_thread_to_folder_job,
     push_flags_job,
+    restore_thread_job,
 )
 from app.sync.engine import bootstrap_and_backfill, refresh_account_job
 
@@ -38,6 +39,7 @@ INTERACTIVE_FUNCTIONS = [
     push_flags_job,
     move_job,
     move_thread_to_folder_job,
+    restore_thread_job,
     delete_thread_job,
     send_job,
     push_draft_to_imap_job,