test: full test suite (Vitest + pgTAP + Playwright) + TDD plan restructure

Add a 4-layer test stack covering RLS, triggers, and UI flows for Fases 0–2a,
then restructure every plan file so future fases start with tests and end with
a verification gate.

Test suite
- packages/test-utils: Vitest integration tests signing HS256 JWTs via jose so
  each test acts as a specific seed user (createClientAs + createAdminClient)
- supabase/tests: pgTAP for accept_invitation(), item_frequency trigger, and
  promote-on-admin-leave; each file self-installs pgtap extension
- apps/web/tests: Playwright E2E with live Keycloak login per test (storageState
  caching doesn't rehydrate Supabase's session state reliably)
- just test-all chains the three suites; test-db forwards POSTGRES_PASSWORD
  as PGPASSWORD with ON_ERROR_STOP=1 so failures abort the chain

Supabase auth gotcha
- PostgREST queries inside onAuthStateChange deadlock on GoTrue's navigator.locks
  auth lock (getAccessToken → getSession → initializePromise waits on the same
  lock that's held during event dispatch). Fix is two defenses: a pass-through
  lock in $lib/supabase, and a setTimeout(0) defer in root +layout.svelte to
  push loadUserCollectives out of the callback's microtask chain. Either alone
  is insufficient; both together unblock the Playwright suite.

Env key rotation
- apps/web/.env.development had a stale demo anon key signed with a different
  secret than root .env; Vite inlined that into the browser bundle so Kong (which
  uses the root .env value) rejected every request with 401. Aligned the two
  files and added a memory entry to flag this for the next rotation.

Plan restructure (TDD)
- Every fase now opens with X.0 Tests primero and closes with X.Z Verificación
  final. Completed fases (0, 1, 2a) show the pattern retroactively with the
  tests that currently cover them; pending fases (2b, 3, 4) list the tests to
  write before implementation.

Docs
- CLAUDE.md status line reports 54 + 12 + 15 = 81 green tests, adds gotchas
  #11 (auth-lock deadlock) and #12 (no storageState caching)
- README.md adds a TDD methodology section and the test-all command
- .gitignore excludes Playwright's generated reports and auth state

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

supabase/tests/003_promote_on_admin_leave.sql

@@ -0,0 +1,72 @@
+-- pgTAP: auto-promote oldest member when sole admin leaves — B-13 (RN-10)
+-- Run with: psql -U postgres -d postgres -f supabase/tests/003_promote_on_admin_leave.sql
+--
+-- The trigger fires on DELETE FROM public.users (user account deletion).
+-- We use a synthetic test user so we don't disturb seed data. The collective
+-- is created by Borja (created_by), so deleting the test admin user doesn't
+-- hit the ON DELETE RESTRICT on collectives.created_by.
+
+CREATE EXTENSION IF NOT EXISTS pgtap;
+
+BEGIN;
+SELECT plan(3);
+
+-- ── Setup ─────────────────────────────────────────────────────────────────────
+-- Use UUIDs outside the seed range (e9...) to avoid collisions.
+INSERT INTO public.users (id, email, display_name, language, avatar_type)
+VALUES ('e9999999-9999-9999-9999-999999999999', 'promote-test@local', 'Promote Admin', 'es', 'initials')
+ON CONFLICT (id) DO NOTHING;
+
+-- Collective owned (created_by) by Borja so the admin-user delete won't be
+-- blocked by ON DELETE RESTRICT on collectives.created_by.
+INSERT INTO public.collectives (id, name, emoji, created_by)
+VALUES ('dddddddd-dddd-dddd-dddd-dddddddddddd',
+        'Promote test collective', '🔄',
+        '22222222-2222-2222-2222-222222222222')
+ON CONFLICT (id) DO NOTHING;
+
+-- Two members: synthetic admin (to be deleted) and Ana as the oldest member.
+INSERT INTO public.collective_members (collective_id, user_id, role, joined_at)
+VALUES
+    ('dddddddd-dddd-dddd-dddd-dddddddddddd',
+     'e9999999-9999-9999-9999-999999999999', 'admin',  now() - INTERVAL '10 days'),
+    ('dddddddd-dddd-dddd-dddd-dddddddddddd',
+     '11111111-1111-1111-1111-111111111111', 'member', now() - INTERVAL '5 days')
+ON CONFLICT (collective_id, user_id) DO NOTHING;
+
+-- B-13a: Initial state — one admin
+SELECT is(
+    (SELECT COUNT(*)::integer FROM public.collective_members
+     WHERE collective_id = 'dddddddd-dddd-dddd-dddd-dddddddddddd'
+     AND role = 'admin'),
+    1,
+    'B-13a: initially one admin in the test collective'
+);
+
+-- ── Fire the trigger: delete the sole admin user ──────────────────────────────
+-- Trigger `promote_on_admin_leave` fires BEFORE DELETE on public.users and
+-- promotes the oldest remaining member (Ana) before the delete cascade removes
+-- the admin's collective_members row.
+DELETE FROM public.users
+WHERE id = 'e9999999-9999-9999-9999-999999999999';
+
+-- B-13b: Ana (oldest remaining) must now be admin
+SELECT results_eq(
+    $$ SELECT role::text FROM public.collective_members
+       WHERE collective_id = 'dddddddd-dddd-dddd-dddd-dddddddddddd'
+       AND   user_id       = '11111111-1111-1111-1111-111111111111' $$,
+    $$ VALUES ('admin') $$,
+    'B-13b: oldest member auto-promoted to admin when sole admin leaves'
+);
+
+-- B-13c: Exactly one admin after promotion
+SELECT is(
+    (SELECT COUNT(*)::integer FROM public.collective_members
+     WHERE collective_id = 'dddddddd-dddd-dddd-dddd-dddddddddddd'
+     AND role = 'admin'),
+    1,
+    'B-13c: exactly one admin after promotion'
+);
+
+SELECT * FROM finish();
+ROLLBACK;