feat: design system overhaul — sidebar, AI chats, settings, brainstorm, color cleanup

- Sidebar: dynamic brand-accent colors, brainstorm section restyled
- AI chat general: popup panel with expand/collapse, hides when contextual AI open
- AI chat contextual: tabs reordered (Actions first), X close button, height fix
- Settings: all tabs restyled, 6 new color presets (sage, terracotta, iron, etc.)
- Global color cleanup: emerald/orange hardcoded → brand-accent dynamic
- Brainstorm page: orange → brand-accent throughout
- PageEntry animation component added to key pages
- Floating AI button: bg-brand-accent instead of hardcoded black
- i18n: all 15 locales updated with new AI/billing keys
- Billing: freemium quota tracking, BYOK, stripe subscription scaffolding
- Admin: integrated into new design
- AGENTS.md + CLAUDE.md project rules added

memento-note/tests/unit/billing-sync.test.ts

@@ -0,0 +1,175 @@
+import { describe, it, expect, vi, beforeEach } from 'vitest';
+import { SubscriptionStatus, SubscriptionTier } from '@prisma/client';
+
+vi.mock('@/lib/prisma', () => ({
+  prisma: {
+    subscription: {
+      upsert: vi.fn().mockResolvedValue({}),
+      findUnique: vi.fn(),
+      findFirst: vi.fn(),
+      update: vi.fn().mockResolvedValue({}),
+    },
+  },
+}));
+
+vi.mock('@/lib/billing/stripe-prices', () => ({
+  priceIdToTier: vi.fn((priceId: string) => {
+    if (priceId === 'price_pro_monthly_test') return 'PRO';
+    if (priceId === 'price_business_monthly_test') return 'BUSINESS';
+    return null;
+  }),
+}));
+
+import { syncSubscriptionFromStripe, handleSubscriptionDeleted } from '@/lib/billing/sync-subscription-from-stripe';
+import { prisma } from '@/lib/prisma';
+import type Stripe from 'stripe';
+
+function makeSubscription(overrides: Partial<Stripe.Subscription> = {}): Stripe.Subscription {
+  return {
+    id: 'sub_test_123',
+    object: 'subscription',
+    status: 'active',
+    customer: 'cus_test_123',
+    current_period_start: 1700000000,
+    current_period_end: 1702678400,
+    cancel_at_period_end: false,
+    canceled_at: null,
+    trial_end: null,
+    metadata: { userId: 'user_test_123', tier: 'PRO' },
+    items: {
+      object: 'list',
+      data: [
+        {
+          id: 'si_test',
+          object: 'subscription_item',
+          price: {
+            id: 'price_pro_monthly_test',
+            object: 'price',
+          } as Stripe.Price,
+        } as Stripe.SubscriptionItem,
+      ],
+      has_more: false,
+      url: '',
+    },
+    ...overrides,
+  } as unknown as Stripe.Subscription;
+}
+
+describe('syncSubscriptionFromStripe', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it('upserts subscription with correct PRO tier from price ID', async () => {
+    const sub = makeSubscription();
+    await syncSubscriptionFromStripe(sub, 'user_test_123');
+
+    expect(prisma.subscription.upsert).toHaveBeenCalledOnce();
+    const call = vi.mocked(prisma.subscription.upsert).mock.calls[0][0];
+    expect(call.where).toEqual({ stripeSubscriptionId: 'sub_test_123' });
+    expect(call.create.tier).toBe(SubscriptionTier.PRO);
+    expect(call.create.status).toBe(SubscriptionStatus.ACTIVE);
+    expect(call.create.userId).toBe('user_test_123');
+    expect(call.create.stripeCustomerId).toBe('cus_test_123');
+    expect(call.create.stripeSubscriptionId).toBe('sub_test_123');
+    expect(call.create.stripePriceId).toBe('price_pro_monthly_test');
+  });
+
+  it('maps stripe active status to ACTIVE', async () => {
+    const sub = makeSubscription({ status: 'active' });
+    await syncSubscriptionFromStripe(sub, 'user_test_123');
+    const call = vi.mocked(prisma.subscription.upsert).mock.calls[0][0];
+    expect(call.create.status).toBe(SubscriptionStatus.ACTIVE);
+  });
+
+  it('maps stripe past_due status to PAST_DUE', async () => {
+    const sub = makeSubscription({ status: 'past_due' });
+    await syncSubscriptionFromStripe(sub, 'user_test_123');
+    const call = vi.mocked(prisma.subscription.upsert).mock.calls[0][0];
+    expect(call.create.status).toBe(SubscriptionStatus.PAST_DUE);
+  });
+
+  it('maps stripe canceled status to CANCELED', async () => {
+    const sub = makeSubscription({ status: 'canceled', canceled_at: 1700100000 });
+    await syncSubscriptionFromStripe(sub, 'user_test_123');
+    const call = vi.mocked(prisma.subscription.upsert).mock.calls[0][0];
+    expect(call.create.status).toBe(SubscriptionStatus.CANCELED);
+    expect(call.create.canceledAt).toBeInstanceOf(Date);
+  });
+
+  it('maps stripe trialing status to TRIALING', async () => {
+    const sub = makeSubscription({ status: 'trialing', trial_end: 1700500000 });
+    await syncSubscriptionFromStripe(sub, 'user_test_123');
+    const call = vi.mocked(prisma.subscription.upsert).mock.calls[0][0];
+    expect(call.create.status).toBe(SubscriptionStatus.TRIALING);
+    expect(call.create.trialEndsAt).toBeInstanceOf(Date);
+  });
+
+  it('maps stripe incomplete_expired to INACTIVE', async () => {
+    const sub = makeSubscription({ status: 'incomplete_expired' });
+    await syncSubscriptionFromStripe(sub, 'user_test_123');
+    const call = vi.mocked(prisma.subscription.upsert).mock.calls[0][0];
+    expect(call.create.status).toBe(SubscriptionStatus.INACTIVE);
+  });
+
+  it('falls back to metadata tier when price ID not in map', async () => {
+    const sub = makeSubscription({
+      metadata: { userId: 'user_test_123', tier: 'BUSINESS' },
+      items: {
+        object: 'list',
+        data: [{ id: 'si_test', object: 'subscription_item', price: { id: 'price_unknown_abc', object: 'price' } as Stripe.Price } as Stripe.SubscriptionItem],
+        has_more: false,
+        url: '',
+      },
+    });
+    await syncSubscriptionFromStripe(sub, 'user_test_123');
+    const call = vi.mocked(prisma.subscription.upsert).mock.calls[0][0];
+    expect(call.create.tier).toBe(SubscriptionTier.BUSINESS);
+  });
+
+  it('sets currentPeriodStart and currentPeriodEnd from Stripe timestamps', async () => {
+    const sub = makeSubscription({
+      current_period_start: 1700000000,
+      current_period_end: 1702678400,
+    });
+    await syncSubscriptionFromStripe(sub, 'user_test_123');
+    const call = vi.mocked(prisma.subscription.upsert).mock.calls[0][0];
+    expect(call.create.currentPeriodStart).toEqual(new Date(1700000000 * 1000));
+    expect(call.create.currentPeriodEnd).toEqual(new Date(1702678400 * 1000));
+  });
+
+  it('sets cancelAtPeriodEnd correctly', async () => {
+    const sub = makeSubscription({ cancel_at_period_end: true });
+    await syncSubscriptionFromStripe(sub, 'user_test_123');
+    const call = vi.mocked(prisma.subscription.upsert).mock.calls[0][0];
+    expect(call.create.cancelAtPeriodEnd).toBe(true);
+  });
+});
+
+describe('handleSubscriptionDeleted', () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it('marks subscription as CANCELED when found', async () => {
+    vi.mocked(prisma.subscription.findUnique).mockResolvedValue({
+      id: 'local_id',
+      stripeSubscriptionId: 'sub_test_123',
+    } as any);
+
+    const sub = makeSubscription({ status: 'canceled', canceled_at: 1700100000 });
+    await handleSubscriptionDeleted(sub);
+
+    expect(prisma.subscription.update).toHaveBeenCalledOnce();
+    const call = vi.mocked(prisma.subscription.update).mock.calls[0][0];
+    expect(call.data.status).toBe(SubscriptionStatus.CANCELED);
+    expect(call.data.cancelAtPeriodEnd).toBe(false);
+  });
+
+  it('does nothing when subscription not found locally', async () => {
+    vi.mocked(prisma.subscription.findUnique).mockResolvedValue(null);
+    const sub = makeSubscription({ status: 'canceled' });
+    await handleSubscriptionDeleted(sub);
+    expect(prisma.subscription.update).not.toHaveBeenCalled();
+  });
+});