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/app/outbox/jobs.py

@@ -24,6 +24,7 @@ from app.indexer.indexer import persist_message
 from app.models import Account, Draft, KnownRecipient, Mailbox, Message, Outbox
 from app.outbox.attachments import load_attachments
 from app.outbox.mime_build import build_mime
+from app.outbox.service import delete_mirrored_draft_row
 from app.providers.base import RemoteMessage
 from app.search.factory import get_search_backend
 from app.sync.provider_factory import build_provider
@@ -178,6 +179,12 @@ async def send_job(ctx: dict[str, Any], outbox_id: str) -> None:
         draft_row = await session.get(Draft, draft.id)
         if draft_row is not None:
             await session.delete(draft_row)
+        # Also drop the mirrored Drafts-folder copy's DB row (we expunged it on the
+        # server above) so it doesn't resurface as a "remote" draft.
+        if draft_imap_uid:
+            await delete_mirrored_draft_row(
+                session, account_id=account_obj.id, imap_uid=draft_imap_uid
+            )
         await _harvest_recipients(session, user_id, envelope_to)
 
     bus = get_event_bus()