Task #402: Convert Notes into in-app messaging

Original task: turn personal Notes into in-app messaging — sender composes
a note (title/content/color), picks recipient(s), Send. Recipients get an
Inbox with sender name, color, Read/Unread badge, and inline reply. Sender
sees Sent Notes with per-recipient status. Sender's and recipient's copies
must be INDEPENDENT, with backend access checks (admin sees everything),
realtime updates, toasts, an unread badge on the Notes app tile, and full
i18n + RTL.

Four review rounds were addressed in this commit:

Round 1 (independence):
- Snapshot columns (title/content/color) on note_recipients; FKs dropped
  on note_recipients.note_id and note_replies.note_id so recipient
  threads survive the sender deleting their note.
- /notes/received and /notes/:id/thread render the recipient snapshot.

Round 2:
- POST /notes/:id/reply: owner is now allowed to reply too.
- Added GET /notes/:id as alias of /notes/:id/thread.
- Added OpenAPI ops for the Notes routes; ran orval codegen.
- use-notifications-socket.ts shows bilingual toasts for note_received /
  note_replied (suppressed during socket warmup).
- home.tsx renders an unread badge on the Notes app tile.

Round 3:
- Archived tab now shows BOTH "My archived notes" and "Archived inbox".
- Sender thread view groups replies by recipient with per-conversation
  header and per-reply author + localized timestamp.
- Send dialog requires explicit AlertDialog confirmation + success toast.
- Realtime toast strings moved off hardcoded EN/AR to i18n keys.
- handleNoteDetail returns 403 (not 404) for non-participants of an
  existing conversation.
- useReplyToNote accepts recipientUserId; ThreadDialog shows a recipient
  picker for owner replies on multi-recipient notes.

Round 5 (this round): admin authorization fix
- handleNoteDetail: admin bypass is now evaluated BEFORE the
  "non-participant 403" branch. When the sender has deleted the live
  note row but recipient snapshots remain, an admin GET /notes/:id now
  returns 200 with thread payload assembled from a fallback recipient
  snapshot (instead of 403).
- New regression test: "admin can read a note whose sender deleted
  their copy (recipient snapshot remains)".

Round 4:
- Added GET /notes/my as an explicit alias of GET /notes (shared
  handleListMyNotes handler).
- Removed `as any[]` cast in /notes/sent — replaced with a precise local
  SentNoteOut type derived from the query result.
- Added auth coverage tests:
  - stranger forbidden from /read, /archive, /reply, GET /notes/:id
  - recipient cannot PATCH the sender's note body
  - admin can read any note via GET /notes/:id and sees full thread
  - GET /notes/my matches GET /notes
  createUser test helper now accepts an optional role.

Note on schema migrations: this monorepo uses `drizzle-kit push` (no
migration files); `pnpm --filter @workspace/db push` was already run
when the new columns/tables landed.

Tests: 11 backend tests in notes-share.test.mjs + 1 e2e (notes-inbox)
all pass. tx-os typecheck is clean. Architect re-review: PASS.

Pre-existing executive-meetings TS errors and the failing top-level
`test` workflow are unrelated to this task.

artifacts/api-server/src/routes/notes.ts

@@ -417,31 +417,57 @@ async function handleNoteDetail(req: import("express").Request, res: import("exp
   const admin = await isAdmin(userId);
   const isSender = !!note && note.userId === userId;
 
-  // Authorization contract: any non-participant gets 403 (not 404), as long
-  // as someone is participating in the conversation. Only return 404 when
-  // there is no trace of the note at all (no live row, no recipient rows).
+  // Authorization contract:
+  //   - admin can read any note that has any trace (live row OR recipient
+  //     snapshots), even if the sender deleted their own copy;
+  //   - non-participants get 403 when the conversation exists but they
+  //     are not part of it;
+  //   - 404 only when there is no trace of the note at all.
+  const [anyRecipientRow] =
+    !note && !recipientRow
+      ? await db
+          .select({ id: noteRecipientsTable.id })
+          .from(noteRecipientsTable)
+          .where(eq(noteRecipientsTable.noteId, id.id))
+          .limit(1)
+      : [null];
+
   if (!note && !recipientRow) {
-    const [otherRow] = await db
-      .select({ id: noteRecipientsTable.id })
-      .from(noteRecipientsTable)
-      .where(eq(noteRecipientsTable.noteId, id.id))
-      .limit(1);
-    if (otherRow) {
+    if (admin && anyRecipientRow) {
+      // fall through — admin reads from recipient snapshots below
+    } else if (anyRecipientRow) {
       res.status(403).json({ error: "Forbidden" });
       return;
+    } else {
+      res.status(404).json({ error: "Note not found" });
+      return;
     }
-    res.status(404).json({ error: "Note not found" });
-    return;
-  }
-  if (!admin && !isSender && !recipientRow) {
+  } else if (!admin && !isSender && !recipientRow) {
     res.status(403).json({ error: "Forbidden" });
     return;
   }
 
+  // For admin reading a deleted note (no live row, no recipient row of
+  // their own), fall back to ANY recipient snapshot so we can still render
+  // the conversation.
+  let adminFallbackRow: typeof recipientRow | null = null;
+  if (admin && !note && !recipientRow) {
+    const [r] = await db
+      .select()
+      .from(noteRecipientsTable)
+      .where(eq(noteRecipientsTable.noteId, id.id))
+      .orderBy(noteRecipientsTable.id)
+      .limit(1);
+    adminFallbackRow = r ?? null;
+  }
+  const snapshotRow = recipientRow ?? adminFallbackRow;
+
   // Recipient view reads its own immutable snapshot. Owner/admin view shows
-  // the live sender note (sender's editable copy).
+  // the live sender note when present; admin falls back to a snapshot when
+  // the live note has been deleted.
   const useSnapshot = !isSender && !admin && !!recipientRow;
-  const senderUserId = note?.userId ?? recipientRow!.senderUserId;
+  const senderUserId =
+    note?.userId ?? recipientRow?.senderUserId ?? snapshotRow?.senderUserId ?? 0;
   const senderMap = await loadUserSummaries([senderUserId]);
 
   const recipients = admin || isSender ? await loadRecipientsForNote(id.id) : [];
@@ -455,15 +481,21 @@ async function handleNoteDetail(req: import("express").Request, res: import("exp
     );
   }
 
+  const titleFallback = snapshotRow?.title ?? note?.title ?? "";
+  const contentFallback = snapshotRow?.content ?? note?.content ?? "";
+  const colorFallback = snapshotRow?.color ?? note?.color ?? "default";
+
   res.json({
     id: id.id,
-    title: useSnapshot ? recipientRow!.title : note?.title ?? "",
-    content: useSnapshot ? recipientRow!.content : note?.content ?? "",
-    color: useSnapshot ? recipientRow!.color : note?.color ?? "default",
-    createdAt: useSnapshot ? recipientRow!.sentAt : note?.createdAt ?? null,
+    title: useSnapshot ? recipientRow!.title : note?.title ?? titleFallback,
+    content: useSnapshot ? recipientRow!.content : note?.content ?? contentFallback,
+    color: useSnapshot ? recipientRow!.color : note?.color ?? colorFallback,
+    createdAt: useSnapshot
+      ? recipientRow!.sentAt
+      : note?.createdAt ?? snapshotRow?.sentAt ?? null,
     updatedAt: useSnapshot
       ? recipientRow!.readAt ?? recipientRow!.sentAt
-      : note?.updatedAt ?? null,
+      : note?.updatedAt ?? snapshotRow?.sentAt ?? null,
     senderUserId,
     sender: senderMap.get(senderUserId) ?? null,
     isOwner: isSender,

artifacts/api-server/tests/notes-share.test.mjs

@@ -460,6 +460,29 @@ test("admin can read any note via GET /notes/:id and sees full thread", async ()
   );
 });
 
+test("admin can read a note whose sender deleted their copy (recipient snapshot remains)", async () => {
+  const sender = await createUser("notes_admdel_sender");
+  const recipient = await createUser("notes_admdel_recipient");
+  const adminUser = await createUser("notes_admdel_admin", "admin");
+  const sCookie = await login(sender.username);
+  const aCookie = await login(adminUser.username);
+
+  const note = await createNote(sCookie, { title: "WillDelete" });
+  await api(`/notes/${note.id}/send`, sCookie, {
+    method: "POST",
+    body: JSON.stringify({ recipientUserIds: [recipient.id] }),
+  });
+  // Sender deletes the live note row; recipient snapshot must remain.
+  await pool.query(`DELETE FROM notes WHERE id = $1`, [note.id]);
+
+  const res = await api(`/notes/${note.id}`, aCookie);
+  assert.equal(res.status, 200, "admin must still read the thread after sender delete");
+  const body = await res.json();
+  assert.equal(body.isAdmin, true);
+  assert.equal(body.title, "WillDelete", "admin sees recipient snapshot title");
+  assert.ok(body.recipients.length >= 1, "admin sees recipient list");
+});
+
 test("GET /notes/my returns the same payload as GET /notes (alias)", async () => {
   const owner = await createUser("notes_my_owner");
   const cookie = await login(owner.username);