Multi-administrator support

1. Summary of changes
The installer-created account is no longer special. "Owner" is now literally renamed Administrator and behaves exactly like the existing role/permission system already allowed — the codebase turned out to already define "administrator" structurally (a StaffProfile whose role holds MANAGE_STAFF), not as a name or a business.ownerId-style field, and last-administrator protection already existed. The real work was: closing the gap between that and a full admin-management UI, fixing two OTP-migration bugs the new spec's requirements exposed, and making the existing protection transactional.

Businesses can now have any number of Administrators, added via Invite Administrator (name + email → OTP-verified before access), promoted/demoted via the existing staff role dropdown (now intercepted with a confirmation dialog when it crosses the Administrator boundary), or removed via the existing deactivate flow.
Two real bugs found and fixed, both required for the spec's "unverified email must not get access":
Invitation acceptance (/invite/accept) never actually verified an OTP — it silently relied on a sign-in path that would have failed for every real invitee. It now sends and verifies a real code, reusing the shared OtpCodeStep UI.
A newly-invited (not-yet-accepted) account could sign in via plain email OTP before ever touching the invite link, because sign-in only checked "does a User row exist," not whether it was verified. Fixed in the shared OTP service, benefiting every invitation, not just administrators'.
Last-administrator protection (already existed) is now transactional — a SELECT ... FOR UPDATE lock on the business row closes the race where two concurrent removals of two different administrators could both succeed.
Administrators (any staff member, in fact) can now change their own email — new address must be OTP-verified before it replaces the login email.
No hidden installer privilege: confirmed via code audit and a live install → the account is a plain Administrator-role staff member, provable identically via the Team UI as any later-added one.
NextChair Manager and platform Super Administrator are untouched.
2. Prisma/database changes
No schema changes. One data-only migration: prisma/migrations/20260905214944_administrator_role_rename — UPDATE Role SET name = 'Administrator' WHERE name = 'Owner' AND isSystem = true. Runs through the normal migration-deploy process; not something to run by hand.

3. How Administrator roles are represented
A per-business Role row named "Administrator" (was "Owner"), isSystem: true, holding every Permission — created identically at install and in dev seed data. This is what "Invite"/"Make Administrator" assign.
Whether a StaffProfile currently counts as an Administrator is permission-based (holds MANAGE_STAFF), not a name check — the same definition the codebase already used for last-owner protection (isStaffAdministrator in staff.service.ts). This is deliberately reused rather than introduced, and stays correct if a business ever gets a custom role that also grants MANAGE_STAFF.
No Business.adminId-style field anywhere — confirmed none existed before this work either.
4. How administrator invitations work
Reuses the existing StaffInvitation model and createStaffProfile/createInvitation machinery verbatim — a new inviteAdministratorAction just pre-selects the Administrator role and uses a minimal Name+Email form (invite-administrator-form.tsx). Acceptance (accept-invitation.ts) now requires a real OTP code sent to the invited email before the account activates — expiry (7 days), resend, and revoke are all the pre-existing invitation mechanics (revoke = the existing deactivate action, relabeled "Revoke Invitation" while pending).

5. How last-administrator protection is enforced
Server-side only, inside staff.service.ts's updateStaffAsOwner (role change) and deactivateStaff (remove), each wrapped in prisma.$transaction that first locks the business row (SELECT ... FOR UPDATE), then counts other active Administrators before allowing the change. Verified with a genuine concurrency test (two simultaneous removals against a 2-admin business) and manually in-browser (see below).

6. Installation flow changes
Only the role name and one line of wizard copy changed ("This becomes the first Administrator..."). No structural UX change — still collects name/email, verifies via OTP, creates/activates the account, assigns the role, exactly as before.

7. Files changed
New: the migration; email-change.service.ts + change-email.ts action + change-email-section.tsx; invite-administrator-form.tsx + add-administrator/page.tsx; 3 new integration test files.

Modified — core: staff.service.ts (transactional protection, isStaffAdministrator), staff-invitation.service.ts, otp.service.ts (onlyIfUserExists fix, email-change purpose), default-permissions.ts, permissions.ts, auth.ts (JWT email-refresh, simplified finalize path).

Modified — actions/UI: owner/actions/staff.ts, staff-detail-panel.tsx, team/page.tsx, add-staff-form.tsx, accept-invitation.ts/form/page, otp-code-step.tsx, profile-form.tsx, installer files, seed.ts, plus a terminology sweep ("owner" → "administrator" copy in breaks.ts/time-off.ts/staff-emails.ts/profile page).

8. Manual testing steps
Sign in as the seeded owner → /owner/team shows an Administrator badge and an "Invite Administrator" icon next to "+". Invite someone, accept via /invite/accept?token=... printed to the terminal (code also prints there) — they land signed in with full Manage access. Promote/demote any staff member via the role dropdown on their detail page — crossing the Administrator boundary shows a confirmation dialog. With only one Administrator left, attempting to demote or deactivate them shows "You can't remove the only administrator. Add another administrator first." Change your own email from Profile settings — the new address must be OTP-verified before it replaces the old one.

9. Deployment steps on the VPS
None beyond the normal deploy process — the migration is a standard Prisma migration that prisma migrate deploy (whatever already runs it there) will pick up automatically. No new environment variables. No changes to NextChair Manager or its authentication.

Verification performed: tsc/lint/unit — all clean; full test:integration — 219 passed (up from 207, all new); full test:e2e — same 36/37 as before this work (the 1 failure is a pre-existing, auth-unrelated flake unrelated to any of this); a full live manual pass covering every scenario above, including the last-administrator block and the email-change JWT-refresh behavior.

src/auth.ts

@@ -14,31 +14,32 @@ import { secretsMatch } from "@/lib/security/secrets-match";
  * src/lib/auth/otp.service.ts's own header for the full verify/finalize
  * design this builds on.
  *
- * `{ email, code }` — normal sign-in/registration: verifyOtp then
- * finalizeOtp back to back in this one request (functionally "verify and
- * consume in one shot" from the caller's point of view).
+ * `{ email, code }` — the normal path, used by sign-in, registration, and
+ * (since the "administrator invite verifies via OTP too" work) invitation
+ * acceptance as well: verifyOtp then finalizeOtp back to back in this one
+ * request (functionally "verify and consume in one shot" from the
+ * caller's point of view).
  *
- * `{ email, finalize: "true", token }` — used only by the installer's and
- * staff-invitation-acceptance's own immediate post-completion sign-in,
- * where the code was already consumed by their own earlier verifyOtp call
- * and can't be re-entered (one-time use). `token` must match either the
- * live INSTALLATION_TOKEN or a valid StaffInvitation.token for this exact
- * email — required because /api/auth/callback/credentials is a public
- * route regardless of this change (true of any Credentials provider), so
- * this path must independently prove the caller already holds a secret an
- * attacker can't have, not just trust that it's being called "from the
- * right place". Without this, a race window (someone else's verifiedAt-
- * but-not-yet-consumedAt row, mid-wizard) would be forgeable via a direct
- * POST to that route with just a guessed email.
+ * `{ email, finalize: "true", token }` — used only by the installer's own
+ * immediate post-completion sign-in, where the administrator's code was
+ * already consumed by installApplication's own earlier verifyOtp call
+ * (inside its transaction) and can't be re-entered (one-time use). `token`
+ * must match the live INSTALLATION_TOKEN — required because
+ * /api/auth/callback/credentials is a public route regardless of this
+ * change (true of any Credentials provider), so this path must
+ * independently prove the caller already holds a secret an attacker can't
+ * have, not just trust that it's being called "from the right place".
+ * Without this, a race window (someone else's verifiedAt-but-not-yet-
+ * consumedAt row, mid-wizard) would be forgeable via a direct POST to that
+ * route with just a guessed email. (Invitation acceptance no longer uses
+ * this path — it has its own real OTP code to re-enter here instead, so
+ * there's nothing left to trust a bare token for there.)
  */
-async function verifyFinalizeToken(email: string, token: string): Promise<boolean> {
+function verifyFinalizeToken(token: string): boolean {
   if (!token) return false;
 
   const installToken = process.env.INSTALLATION_TOKEN;
-  if (installToken && secretsMatch(token, installToken)) return true;
-
-  const invitation = await prisma.staffInvitation.findUnique({ where: { token }, select: { email: true } });
-  return !!invitation && invitation.email.toLowerCase() === email;
+  return !!installToken && secretsMatch(token, installToken);
 }
 
 export const { handlers, auth, signIn, signOut } = NextAuth({
@@ -56,9 +57,9 @@ export const { handlers, auth, signIn, signOut } = NextAuth({
       credentials: {
         email: { label: "Email", type: "email" },
         code: { label: "Code", type: "text" },
-        // Only ever set by trusted server-side callers (the installer,
-        // staff-invitation acceptance) — never rendered on any real form.
-        // See this file's own header for the full finalize/token design.
+        // Only ever set by the installer's own trusted server-side sign-in
+        // call — never rendered on any real form. See this file's own
+        // header for the full finalize/token design.
         finalize: { label: "Finalize", type: "text" },
         token: { label: "Token", type: "text" },
       },
@@ -76,8 +77,7 @@ export const { handlers, auth, signIn, signOut } = NextAuth({
 
         if (raw?.finalize === "true") {
           const token = typeof raw?.token === "string" ? raw.token : "";
-          const trusted = await verifyFinalizeToken(email, token);
-          if (!trusted) return null;
+          if (!verifyFinalizeToken(token)) return null;
           if (!(await finalizeOtp(prisma, email))) return null;
         } else {
           const code = typeof raw?.code === "string" ? raw.code : "";
@@ -95,10 +95,22 @@ export const { handlers, auth, signIn, signOut } = NextAuth({
     }),
   ],
   callbacks: {
-    async jwt({ token, user }) {
+    async jwt({ token, user, trigger, session }) {
       if (user?.id) {
         token.id = user.id;
       }
+      // Lets a client-side `useSession().update({ email })` call (see
+      // change-email.ts's verifyEmailChangeAction, whose caller triggers
+      // this right after a successful email change) refresh the JWT's own
+      // email claim without forcing a full sign-out/sign-in — otherwise
+      // session.user.email would keep showing the old address until the
+      // token's next natural refresh. Nothing else in this app reads
+      // session.user.email for authorization (every permission/tenant
+      // check is keyed on token.id/session.user.id), so this is purely a
+      // display-freshness fix.
+      if (trigger === "update" && typeof session?.email === "string") {
+        token.email = session.email;
+      }
       return token;
     },
     async session({ session, token }) {