backend: add per-clinic staff specialty (Care Team -> patient sheet)

New staff_profile table (org + user, unique) holding a clinician's clinical
specialty. GET /api/staff and /api/staff/providers now include specialty; new
PATCH /api/staff/:userId (member:update) upserts it. Migration 0023.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

backend/src/db/schema/index.ts

@@ -16,3 +16,4 @@ export * from "./ai-chat.js";
 export * from "./org-ai-policy.js";
 export * from "./attachments.js";
 export * from "./integrations.js";
+export * from "./staff-profile.js";

backend/src/db/schema/staff-profile.ts

@@ -0,0 +1,31 @@
+import { pgTable, text, timestamp, uniqueIndex } from "drizzle-orm/pg-core";
+
+import { organization, user } from "./auth.js";
+
+// Per-member, per-clinic profile extras that Better Auth's member row doesn't
+// hold. Currently just a doctor's clinical specialty (e.g. "Orthopedist",
+// "Dentist") which the admin sets in Care Team and surfaces on the patient
+// sheet for the patient's primary provider. Unique on (org, user) so each
+// member has at most one profile per clinic.
+export const staffProfile = pgTable(
+  "staff_profile",
+  {
+    organizationId: text("organization_id")
+      .notNull()
+      .references(() => organization.id, { onDelete: "cascade" }),
+    userId: text("user_id")
+      .notNull()
+      .references(() => user.id, { onDelete: "cascade" }),
+    specialty: text("specialty"),
+    updatedAt: timestamp("updated_at")
+      .defaultNow()
+      .$onUpdate(() => new Date())
+      .notNull(),
+  },
+  (table) => [
+    uniqueIndex("staff_profile_org_user_idx").on(
+      table.organizationId,
+      table.userId,
+    ),
+  ],
+);