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>

client/node_modules/browserslist/README.md

@@ -0,0 +1,65 @@
+# Browserslist
+
+<img width="120" height="120" alt="Browserslist logo by Anton Popov"
+     src="https://browsersl.ist/logo.svg" align="right">
+
+The config to share target browsers and Node.js versions between different
+front-end tools. It is used in:
+
+* [Autoprefixer]
+* [Babel]
+* [postcss-preset-env]
+* [eslint-plugin-compat]
+* [stylelint-no-unsupported-browser-features]
+* [postcss-normalize]
+* [obsolete-webpack-plugin]
+
+All tools will find target browsers automatically,
+when you add the following to `package.json`:
+
+```json
+  "browserslist": [
+    "defaults and fully supports es6-module",
+    "maintained node versions"
+  ]
+```
+
+Or in `.browserslistrc` config:
+
+```yaml
+# Browsers that we support
+
+defaults and fully supports es6-module
+maintained node versions
+```
+
+Developers set their version lists using queries like `last 2 versions`
+to be free from updating versions manually.
+Browserslist will use [`caniuse-lite`] with [Can I Use] data for this queries.
+
+You can check how config works at our playground: [`browsersl.ist`](https://browsersl.ist/)
+
+<a href="https://browsersl.ist/">
+  <img src="/img/screenshot.webp" alt="browsersl.ist website">
+</a>
+
+<br>
+<br>
+<div align="center">
+  <a href="https://evilmartians.com/?utm_source=browserslist"><img src="https://evilmartians.com/badges/sponsored-by-evil-martians.svg" alt="Sponsored by Evil Martians" width="236" height="54"></a>  <a href="https://cube.dev/?ref=eco-browserslist-github"><img src="https://user-images.githubusercontent.com/986756/154330861-d79ab8ec-aacb-4af8-9e17-1b28f1eccb01.svg" alt="Supported by Cube" width="227" height="46"></a>
+</div>
+
+[stylelint-no-unsupported-browser-features]: https://github.com/ismay/stylelint-no-unsupported-browser-features
+[obsolete-webpack-plugin]:                   https://github.com/ElemeFE/obsolete-webpack-plugin
+[eslint-plugin-compat]:                      https://github.com/amilajack/eslint-plugin-compat
+[Browserslist Example]:                      https://github.com/browserslist/browserslist-example
+[postcss-preset-env]:                        https://github.com/csstools/postcss-plugins/tree/main/plugin-packs/postcss-preset-env
+[postcss-normalize]:                         https://github.com/csstools/postcss-normalize
+[`browsersl.ist`]:                           https://browsersl.ist/
+[`caniuse-lite`]:                            https://github.com/ben-eb/caniuse-lite
+[Autoprefixer]:                              https://github.com/postcss/autoprefixer
+[Can I Use]:                                 https://caniuse.com/
+[Babel]:                                     https://github.com/babel/babel/tree/master/packages/babel-preset-env
+
+## Docs
+Read full docs **[here](https://github.com/browserslist/browserslist#readme)**.