feat: complete ShiftCraft — AI-powered shift scheduling SaaS

Complete implementation including:
- Landing page with hero, features, how-it-works, pricing
- Employee management (CRUD with soft delete)
- AI constraint parser (Anthropic Claude API)
- German labor law templates (ArbZG §3, §5, §9)
- HiGHS ILP solver for optimal fair schedules
- Schedule calendar result view (employee × date grid)
- Shift framework configuration (periods + shifts)
- Subscription tiers: Free / Pro / Business
- PocketBase setup script with collection creation + seed data
- .env.example with all required variables documented

Pages: employees, constraints (list/new/templates), schedules (list/new/[id]),
       settings (organization/shifts/billing), dashboard

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

app/utils/planLimits.ts

@@ -0,0 +1,67 @@
+export const PLAN_LIMITS = {
+  free: {
+    name: 'Free',
+    price_eur_month: 0,
+    employee_limit: 5,
+    history_months: 1,
+    solve_runs_per_month: 10,
+    ai_parses_per_month: 20,
+    legal_templates: true,
+    pdf_export: false,
+    excel_export: false,
+    support: 'community',
+    stripe_price_id: null,
+    description: 'Für kleine Teams zum Ausprobieren',
+    features: [
+      'Bis zu 5 Mitarbeiter',
+      '10 Schichtpläne/Monat',
+      'Gesetzliche Vorlagen (Deutschland)',
+      'KI-Bedingungserkennung',
+    ],
+  },
+  pro: {
+    name: 'Pro',
+    price_eur_month: 29,
+    employee_limit: 25,
+    history_months: 6,
+    solve_runs_per_month: 100,
+    ai_parses_per_month: 200,
+    legal_templates: true,
+    pdf_export: true,
+    excel_export: true,
+    support: 'email',
+    stripe_price_id: 'price_pro_monthly',
+    description: 'Für wachsende Teams',
+    features: [
+      'Bis zu 25 Mitarbeiter',
+      '100 Schichtpläne/Monat',
+      'PDF & Excel Export',
+      '6 Monate Verlauf',
+      'E-Mail Support',
+    ],
+  },
+  business: {
+    name: 'Business',
+    price_eur_month: 99,
+    employee_limit: Infinity,
+    history_months: Infinity,
+    solve_runs_per_month: Infinity,
+    ai_parses_per_month: Infinity,
+    legal_templates: true,
+    pdf_export: true,
+    excel_export: true,
+    support: 'priority',
+    stripe_price_id: 'price_business_monthly',
+    description: 'Für große Unternehmen',
+    features: [
+      'Unbegrenzte Mitarbeiter',
+      'Unbegrenzte Schichtpläne',
+      'PDF & Excel Export',
+      'Unbegrenzter Verlauf',
+      'Priority Support',
+      'API-Zugang (demnächst)',
+    ],
+  },
+} as const
+
+export type PlanTier = keyof typeof PLAN_LIMITS