Task #670: revamp public room-booking form (protocol)

Public booking form now captures department, meeting type (internal/
external), meeting purpose, and a repeatable "key attendees" table
(name + position + side). External meetings require the entity name
(reuses requesterOrg). "عدد الحضور" relabeled to "العدد المتوقع للحضور".
Added a static red disclaimer note about possible cancellation.

Each booking now gets an auto-generated searchable reference
(RB-{year}-{pad4}) shown on the success screen; staff can search the
admin bookings list by reference OR phone.

Changes:
- lib/db schema: department, meetingType, purpose, keyAttendees (jsonb),
  bookingReference (unique) + requesterPhone index; new enums/types.
  Applied via drizzle push; backfilled existing 4 rows.
- api-server: extended public booking schema + refine (org required when
  external), makeBookingReference, public/internal POST generate+return
  bookingReference.
- tx-os public form rewritten; admin card shows new fields + client-side
  search with empty state.
- ar/en i18n keys under protocol.bookings.

Notes:
- Pre-existing push.ts typecheck errors are unrelated to this task.
- Architect review: PASS, no blocking issues.

lib/db/src/schema/protocol.ts

@@ -8,6 +8,7 @@ import {
   jsonb,
   boolean,
   index,
+  uniqueIndex,
 } from "drizzle-orm/pg-core";
 import { createInsertSchema } from "drizzle-zod";
 import { z } from "zod/v4";
@@ -35,6 +36,25 @@ export const PROTOCOL_BOOKING_STATUSES = [
 export type ProtocolBookingStatus =
   (typeof PROTOCOL_BOOKING_STATUSES)[number];
 
+// A room booking is either an internal meeting or a meeting with an external
+// entity. When external, the requester's organization (requesterOrg / اسم
+// الجهة) is required.
+export const PROTOCOL_MEETING_TYPES = ["internal", "external"] as const;
+export type ProtocolMeetingType = (typeof PROTOCOL_MEETING_TYPES)[number];
+
+// Which "side" a key attendee belongs to: from the authority (من الهيئة) or
+// from outside it (خارج الهيئة).
+export const PROTOCOL_ATTENDEE_SIDES = ["internal", "external"] as const;
+export type ProtocolAttendeeSide = (typeof PROTOCOL_ATTENDEE_SIDES)[number];
+
+// A notable attendee ("أبرز الحضور") captured on the booking request. Stored
+// as a JSON array on the booking row.
+export type ProtocolKeyAttendee = {
+  name: string;
+  position: string;
+  side: ProtocolAttendeeSide;
+};
+
 export const PROTOCOL_ISSUE_STATUSES = [
   "pending",
   "approved",
@@ -94,9 +114,26 @@ export const protocolRoomBookingsTable = pgTable(
     // The requester's organization / entity (الجهة). Optional even for
     // public requests; always null for internal bookings unless set.
     requesterOrg: varchar("requester_org", { length: 300 }),
-    // Expected number of attendees (عدد الحضور). Optional; supplied by the
-    // guest on a public request or by staff on an internal booking.
+    // Expected number of attendees (العدد المتوقع للحضور). Optional; supplied
+    // by the guest on a public request or by staff on an internal booking.
     attendeeCount: integer("attendee_count"),
+    // The requester's department / administration (الإدارة). Optional.
+    department: varchar("department", { length: 300 }),
+    // Whether the meeting is internal or with an external entity. When
+    // "external", requesterOrg (اسم الجهة) is required. Defaults to internal.
+    meetingType: varchar("meeting_type", { length: 20 })
+      .notNull()
+      .default("internal"),
+    // Free-text purpose of the meeting (الغرض من الاجتماع). Optional.
+    purpose: text("purpose"),
+    // Notable attendees (أبرز الحضور): array of { name, position, side }.
+    keyAttendees: jsonb("key_attendees")
+      .$type<ProtocolKeyAttendee[]>()
+      .notNull()
+      .default([]),
+    // Human-friendly, unique booking reference (رقم الحجز) shown to the
+    // requester on success and searchable by staff. Generated on insert.
+    bookingReference: varchar("booking_reference", { length: 40 }),
     // Provenance marker. "internal" for bookings created by authenticated
     // protocol staff through the app; "public" for guest requests coming in
     // via the no-login booking-request link. Defaults to "internal" so all
@@ -128,6 +165,10 @@ export const protocolRoomBookingsTable = pgTable(
     roomIdx: index("protocol_bookings_room_idx").on(t.roomId),
     startIdx: index("protocol_bookings_start_idx").on(t.startsAt),
     statusIdx: index("protocol_bookings_status_idx").on(t.status),
+    referenceIdx: uniqueIndex("protocol_bookings_reference_idx").on(
+      t.bookingReference,
+    ),
+    phoneIdx: index("protocol_bookings_phone_idx").on(t.requesterPhone),
   }),
 );