Release 0.17.0: admin-create user + invite email (+ #21 Part C Amplitude wiring)

Wave 5. Roadmap item #16. Folds in #21 Part C Amplitude wiring inline.

From the v0.9.0 /admin/users surface, an admin can create a fresh
users row, assign a role (admin/owner/granted-beta-user), include
an optional custom message, and dispatch an invite email carrying
a single-use opaque claim token (256-bit CSPRNG, bcrypt-at-rest,
7-day TTL). The invitee clicks through, lands at /invites/claim,
optionally checks "trust this device for 30 days", and is signed
in without going through OTC (the token in the email is itself
proof of email control).

Backend: migration 019_user_invite_tokens.sql (auto-applied);
backend/app/invites.py (create + claim + list module);
backend/app/email_invite.py (sibling of email_otc); POST
/api/admin/users + GET /api/admin/users/invites in api_admin;
POST /api/invites/claim in main.py's oauth_router (shares
trust-device cookie helper with /auth/otc/verify). 15 new tests in
test_admin_create_user_invite_vertical.py. permission_events row
with event_kind='user_invited' for the audit trail.

Frontend: Admin.jsx Create-user-invite modal + (pending invite)
badge in UserRow; InviteClaim.jsx /invites/claim landing page.
App.jsx route registration. api.js helpers.

Design choices documented in the CHANGELOG: immediate-send (no
admin-review queue); no bulk-invite (deferred); OTC skipped on
first sign-in (token = proof of email control); no users table
changes (discriminator is active user_invite_tokens row, not a
new first_sign_in_at column); refusal cases (self-invite 422,
duplicate email 409, non-owner admin granting owner 422).

Amplitude wiring (inline, #21 Part C):
  - USER_INVITED from CreateUserInviteModal { target_user_id,
    initial_role, custom_message_chars }
  - INVITE_CLAIMED from InviteClaim { invited_by_admin_id,
    initial_role, needs_passcode, trust_device }
  - identify() BEFORE the claim event with properties:
    claim_method 'admin-invite', invited_at (setOnce),
    invited_by_admin_id (setOnce), initial_role (setOnce) —
    so the Amplitude user record is created with the OHM
    user_id from the very first event the invitee fires

Subagent ο shipped the feature on feature/v0.17.0-admin-create-user
(41b0c6a). Driver-side integration squash-merged into main,
hand-resolved 5 files (VERSION, package.json, CHANGELOG —
strict-descending to 0.17.0 → 0.16.0 → 0.15.0; App.jsx — both
new routes kept; api_admin.py — both per-user additive fields
+ pending-invite query both kept). Added inline Amplitude wiring
in CreateUserInviteModal + InviteClaim. 252 backend tests pass
(33 new across #12 + #16 surfaces). Frontend build verified green.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

frontend/src/api.js

@@ -799,6 +799,53 @@ export async function removeAllowlistEmail(email) {
   }))
 }
 
+// v0.17.0 — roadmap item #16. Admin-create user + invite email with
+// optional custom message. The frontend modal on /admin/users wires
+// these two helpers; the claim helper drives the /invites/claim page
+// that the invitee lands on when they click the email link.
+//
+// `createUserInvite` returns `{ ok, invite_id, invited_user_id, email,
+// role }`. The 409 path (duplicate email) and 422 path (self-invite,
+// owner-grant-by-non-owner, malformed input) surface as thrown errors
+// via `jsonOrThrow` so the modal can render the server's message.
+//
+// `listUserInvites` returns the active-invites list for the admin's
+// "I sent these but they haven't been claimed yet" view. Active means
+// not claimed and not expired; once the invitee clicks through, the
+// row clears here and the user-listing's `pending_invite` badge
+// vanishes alongside.
+
+export async function createUserInvite({ email, first_name, last_name, role, custom_message }) {
+  return jsonOrThrow(await fetch('/api/admin/users', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({
+      email,
+      first_name: first_name || '',
+      last_name: last_name || '',
+      role,
+      custom_message: custom_message || '',
+    }),
+  }))
+}
+
+export async function listUserInvites() {
+  return jsonOrThrow(await fetch('/api/admin/users/invites'))
+}
+
+// Claim an admin-issued invite token. Anonymous endpoint — the invitee
+// is not yet signed in; this call establishes the session on success.
+// `trustDevice` mirrors the v0.11.0 OTC/passcode opt-in: when true,
+// the server mints a fresh device-trust row + sets the long-lived
+// cookie so the invitee skips OTC on their next visit.
+export async function claimInvite(token, { trustDevice = false } = {}) {
+  return jsonOrThrow(await fetch('/api/invites/claim', {
+    method: 'POST',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify({ token, trust_device: !!trustDevice }),
+  }))
+}
+
 export async function searchUsers(q) {
   const params = new URLSearchParams()
   if (q) params.set('q', q)