fix(email): draft lifecycle, keyboard nav, and composer layout fixes from review

- Remove the "Mark as read" toggle for Everything else end-to-end (UI, IPC,
  config, sync auto-read, markSectionRead) — it could bulk-mark backlog and
  archived mail read on the server during cache-recovery syncs
- Sending an edited draft now reuses the draft's stored In-Reply-To/References
  instead of self-referencing its own Message-ID (external clients thread
  correctly); standalone drafts send as fresh messages
- Keep draft autosaves out of the sync pipeline: skip DRAFT history messages
  (no more md/knowledge-event leaks, phantom "New email" notifications, or
  per-autosave LLM reclassification) and mirror the draft body onto the cached
  snapshot surgically instead of waking the sync loop
- Only recreate a Gmail draft when update fails with 404/410 — transient
  errors no longer pile up duplicates
- Emptying a draft and closing now deletes it from Gmail (matches Gmail)
- Forward keydown out of message iframes so j/k/e/r etc. keep working after
  clicking into an email body; restore expanded quotes across theme reloads
- Composer footer wraps on narrow panes: formatting toolbar + Discard move as
  one unit instead of overflowing into each other

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

apps/x/packages/shared/src/blocks.ts

@@ -130,6 +130,12 @@ export const GmailThreadMessageSchema = z.object({
   messageIdHeader: z.string().optional(),
   // Set on the unsent draft message within a thread (used by the Drafts view).
   isDraft: z.boolean().optional(),
+  // The draft's own stored In-Reply-To / References headers. Only set on
+  // draft messages: a Drafts-view pseudo-thread contains just the draft, so
+  // the composer can't rebuild the reply chain from thread messages and must
+  // reuse what the draft already carries.
+  inReplyToHeader: z.string().optional(),
+  referencesHeader: z.string().optional(),
 });
 
 export type GmailThreadMessage = z.infer<typeof GmailThreadMessageSchema>;