test(auth,payments,subs): add 58 unit tests for critical auth, payment, and subscription paths

Cover auth handlers (RegisterUser, LoginUser, RefreshToken), TokenService
(token rotation, reuse attack detection), payment callback edge cases
(duplicate/concurrent callbacks, multi-provider), subscription lifecycle
transitions (expire, pastDue, renew), and throttler proxy guard.

Co-Authored-By: Paperclip <noreply@paperclip.ing>

e2e/global-setup.ts

@@ -0,0 +1,55 @@
+/* eslint-disable no-console */
+import { execSync } from 'node:child_process';
+import path from 'node:path';
+
+/**
+ * Playwright globalSetup — runs once before all E2E tests.
+ *
+ * 1. Loads .env.test (if present) so DATABASE_URL points to the test DB.
+ * 2. Runs Prisma migrations against the test database.
+ * 3. Seeds the test database with sample data.
+ */
+export default async function globalSetup() {
+  const root = path.resolve(__dirname, '..');
+  const envTestPath = path.join(root, '.env.test');
+  const isCI = !!process.env.CI;
+
+  // In CI, env vars are already set by the workflow; locally, load .env.test
+  if (!isCI) {
+    const { config } = await import('dotenv');
+    config({ path: envTestPath, override: true });
+  }
+
+  const databaseUrl = process.env.DATABASE_URL;
+  if (!databaseUrl) {
+    throw new Error(
+      'DATABASE_URL is not set. Create .env.test or set it in your environment.',
+    );
+  }
+
+  // In CI, the workflow already runs migrations + seed before Playwright.
+  // Skip to avoid duplicate work; only validate DATABASE_URL is set.
+  if (isCI) {
+    console.log('[E2E globalSetup] CI detected — skipping migrations/seed (handled by workflow).');
+    return;
+  }
+
+  console.log('\n[E2E globalSetup] Preparing test database...');
+  console.log(`[E2E globalSetup] DATABASE_URL = ${databaseUrl.replace(/\/\/.*@/, '//***@')}`);
+
+  const execOpts = {
+    cwd: root,
+    stdio: 'inherit' as const,
+    env: { ...process.env, DATABASE_URL: databaseUrl },
+  };
+
+  // Run migrations (deploy = no interactive prompts, safe for test)
+  console.log('[E2E globalSetup] Running prisma migrate deploy...');
+  execSync('npx prisma migrate deploy', execOpts);
+
+  // Seed database (upserts are idempotent)
+  console.log('[E2E globalSetup] Seeding test database...');
+  execSync('npx prisma db seed', execOpts);
+
+  console.log('[E2E globalSetup] Test database ready.\n');
+}