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/001_accept_invitation.sql

@@ -0,0 +1,91 @@
+-- pgTAP: accept_invitation() function — B-series edge cases
+-- Run with: psql -U postgres -d postgres -f supabase/tests/001_accept_invitation.sql
+
+CREATE EXTENSION IF NOT EXISTS pgtap;
+
+BEGIN;
+SELECT plan(6);
+
+-- Setup: three invitations (valid, already-used, expired).
+-- NOTE: accept_invitation() looks up by `token`, not by `id`.
+DO $$
+BEGIN
+    INSERT INTO public.collective_invitations (id, collective_id, token, created_by, role, expires_at)
+    VALUES
+        ('ffffffff-0001-0001-0001-000000000001',
+         'aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa',
+         'ffffffff-0001-0001-0001-000000000001', -- token = same UUID for convenience
+         '11111111-1111-1111-1111-111111111111',
+         'member',
+         now() + INTERVAL '7 days'),
+        ('ffffffff-0002-0002-0002-000000000002',
+         'aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa',
+         'ffffffff-0002-0002-0002-000000000002',
+         '11111111-1111-1111-1111-111111111111',
+         'member',
+         now() + INTERVAL '7 days'),
+        ('ffffffff-0003-0003-0003-000000000003',
+         'aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa',
+         'ffffffff-0003-0003-0003-000000000003',
+         '11111111-1111-1111-1111-111111111111',
+         'member',
+         now() - INTERVAL '1 day')
+    ON CONFLICT (id) DO NOTHING;
+
+    -- Mark the second one as already used
+    UPDATE public.collective_invitations
+    SET    accepted_at = now(),
+           accepted_by = '22222222-2222-2222-2222-222222222222'
+    WHERE  id = 'ffffffff-0002-0002-0002-000000000002';
+END $$;
+
+-- Make auth.uid() resolve to Eva. set_config() is more reliable than `SET LOCAL`.
+SELECT set_config('request.jwt.claim.sub', '55555555-5555-5555-5555-555555555555', true);
+
+-- B-10: Accept valid invitation
+SELECT results_eq(
+    $$ SELECT (public.accept_invitation('ffffffff-0001-0001-0001-000000000001'::uuid) ->> 'ok')::boolean $$,
+    $$ VALUES (true) $$,
+    'B-10: valid invitation accepted'
+);
+
+SELECT ok(
+    EXISTS (
+        SELECT 1 FROM public.collective_members
+        WHERE collective_id = 'aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa'
+        AND   user_id       = '55555555-5555-5555-5555-555555555555'
+    ),
+    'B-10: Eva added to collective_members after acceptance'
+);
+
+-- B-11: Already-used invitation returns already_used
+SELECT results_eq(
+    $$ SELECT public.accept_invitation('ffffffff-0002-0002-0002-000000000002'::uuid) ->> 'error' $$,
+    $$ VALUES ('already_used') $$,
+    'B-11: already-used invitation returns already_used error'
+);
+
+-- B-12: Expired invitation returns expired
+SELECT results_eq(
+    $$ SELECT public.accept_invitation('ffffffff-0003-0003-0003-000000000003'::uuid) ->> 'error' $$,
+    $$ VALUES ('expired') $$,
+    'B-12: expired invitation returns expired error'
+);
+
+-- B-12b: Non-existent token returns not_found
+SELECT results_eq(
+    $$ SELECT public.accept_invitation('00000000-0000-0000-0000-000000000000'::uuid) ->> 'error' $$,
+    $$ VALUES ('not_found') $$,
+    'B-12b: non-existent token returns not_found error'
+);
+
+-- B-12c: Accepting the same token twice — already-used takes precedence over
+-- already_member (the function checks accepted_at before membership).
+SELECT results_eq(
+    $$ SELECT public.accept_invitation('ffffffff-0001-0001-0001-000000000001'::uuid) ->> 'error' $$,
+    $$ VALUES ('already_used') $$,
+    'B-12c: re-using a consumed invitation returns already_used'
+);
+
+SELECT * FROM finish();
+ROLLBACK;