feat: Initial implementation of Annas Rechnungsmanager

Full-stack German accounting & invoice management web application:

- Multi-company management (Mandantenverwaltung) with full CRUD
- Invoice creation with dynamic line items and automatic tax calculation
- Sequential invoice numbering per company (RE-2024-001 format)
- §14 UStG compliant PDF invoice generation via @react-pdf/renderer
- Customer management (Kundenverwaltung) per company
- Tax reports: quarterly USt-Voranmeldung and monthly revenue overview
- Email/password authentication via NextAuth.js v5
- Responsive, modern UI with Tailwind CSS and custom shadcn/ui components
- Prisma v5 ORM with MySQL/MariaDB schema + demo seed data

Stack: Next.js 14 (App Router) · TypeScript · Prisma/MySQL · NextAuth.js

https://claude.ai/code/session_01FN53KKxo5ebrGwqFhxzkT9

package.json

@@ -0,0 +1,54 @@
+{
+  "name": "annas-app",
+  "version": "0.1.0",
+  "private": true,
+  "scripts": {
+    "dev": "next dev",
+    "build": "next build",
+    "start": "next start",
+    "lint": "eslint",
+    "db:migrate": "prisma migrate dev",
+    "db:seed": "ts-node --compiler-options '{\"module\":\"CommonJS\"}' prisma/seed.ts",
+    "db:studio": "prisma studio"
+  },
+  "prisma": {
+    "seed": "npx ts-node --compiler-options {\"module\":\"CommonJS\"} prisma/seed.ts"
+  },
+  "dependencies": {
+    "@auth/prisma-adapter": "^2.11.1",
+    "@hookform/resolvers": "^5.2.2",
+    "@prisma/client": "^5.22.0",
+    "@radix-ui/react-dialog": "^1.1.15",
+    "@radix-ui/react-dropdown-menu": "^2.1.16",
+    "@radix-ui/react-label": "^2.1.8",
+    "@radix-ui/react-select": "^2.2.6",
+    "@radix-ui/react-separator": "^1.1.8",
+    "@radix-ui/react-slot": "^1.2.4",
+    "@radix-ui/react-toast": "^1.2.15",
+    "@react-pdf/renderer": "^4.3.2",
+    "@types/bcryptjs": "^2.4.6",
+    "bcryptjs": "^3.0.3",
+    "class-variance-authority": "^0.7.1",
+    "clsx": "^2.1.1",
+    "date-fns": "^4.1.0",
+    "lucide-react": "^0.577.0",
+    "next": "16.1.6",
+    "next-auth": "^5.0.0-beta.30",
+    "prisma": "^5.22.0",
+    "react": "19.2.3",
+    "react-dom": "19.2.3",
+    "react-hook-form": "^7.71.2",
+    "tailwind-merge": "^3.5.0",
+    "zod": "^4.3.6"
+  },
+  "devDependencies": {
+    "@tailwindcss/postcss": "^4",
+    "@types/node": "^20",
+    "@types/react": "^19",
+    "@types/react-dom": "^19",
+    "eslint": "^9",
+    "eslint-config-next": "16.1.6",
+    "tailwindcss": "^4",
+    "typescript": "^5"
+  }
+}