Add Milestones 1 & 2: full-stack POS foundation with admin UI

- Node/Express/TypeScript API under /api/v1 with JWT auth (login, refresh, logout, /me)
- Prisma schema: vendors, users, roles, products, categories, taxes, transactions
- SQLite for local dev; Postgres via docker-compose for production
- Full CRUD routes for vendors, users, categories, taxes, products with Zod validation and RBAC
- Paginated list endpoints scoped per vendor; refresh token rotation
- React/TypeScript admin SPA (Vite): login, protected routing, sidebar layout
- Pages: Dashboard, Catalog (tabbed Products/Categories/Taxes), Users, Vendor Settings
- Shared UI: Table, Modal, FormField, Btn, PageHeader components
- Multi-stage Dockerfile; docker-compose with Postgres healthcheck
- Seed script with demo vendor and owner account
- INSTRUCTIONS.md, ROADMAP.md, .claude/launch.json for dev server config

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

server/node_modules/jsonwebtoken/lib/JsonWebTokenError.js

@@ -0,0 +1,14 @@
+var JsonWebTokenError = function (message, error) {
+  Error.call(this, message);
+  if(Error.captureStackTrace) {
+    Error.captureStackTrace(this, this.constructor);
+  }
+  this.name = 'JsonWebTokenError';
+  this.message = message;
+  if (error) this.inner = error;
+};
+
+JsonWebTokenError.prototype = Object.create(Error.prototype);
+JsonWebTokenError.prototype.constructor = JsonWebTokenError;
+
+module.exports = JsonWebTokenError;