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/iconv-lite/lib/streams.js

@@ -0,0 +1,121 @@
+"use strict";
+
+var Buffer = require("buffer").Buffer,
+    Transform = require("stream").Transform;
+
+
+// == Exports ==================================================================
+module.exports = function(iconv) {
+    
+    // Additional Public API.
+    iconv.encodeStream = function encodeStream(encoding, options) {
+        return new IconvLiteEncoderStream(iconv.getEncoder(encoding, options), options);
+    }
+
+    iconv.decodeStream = function decodeStream(encoding, options) {
+        return new IconvLiteDecoderStream(iconv.getDecoder(encoding, options), options);
+    }
+
+    iconv.supportsStreams = true;
+
+
+    // Not published yet.
+    iconv.IconvLiteEncoderStream = IconvLiteEncoderStream;
+    iconv.IconvLiteDecoderStream = IconvLiteDecoderStream;
+    iconv._collect = IconvLiteDecoderStream.prototype.collect;
+};
+
+
+// == Encoder stream =======================================================
+function IconvLiteEncoderStream(conv, options) {
+    this.conv = conv;
+    options = options || {};
+    options.decodeStrings = false; // We accept only strings, so we don't need to decode them.
+    Transform.call(this, options);
+}
+
+IconvLiteEncoderStream.prototype = Object.create(Transform.prototype, {
+    constructor: { value: IconvLiteEncoderStream }
+});
+
+IconvLiteEncoderStream.prototype._transform = function(chunk, encoding, done) {
+    if (typeof chunk != 'string')
+        return done(new Error("Iconv encoding stream needs strings as its input."));
+    try {
+        var res = this.conv.write(chunk);
+        if (res && res.length) this.push(res);
+        done();
+    }
+    catch (e) {
+        done(e);
+    }
+}
+
+IconvLiteEncoderStream.prototype._flush = function(done) {
+    try {
+        var res = this.conv.end();
+        if (res && res.length) this.push(res);
+        done();
+    }
+    catch (e) {
+        done(e);
+    }
+}
+
+IconvLiteEncoderStream.prototype.collect = function(cb) {
+    var chunks = [];
+    this.on('error', cb);
+    this.on('data', function(chunk) { chunks.push(chunk); });
+    this.on('end', function() {
+        cb(null, Buffer.concat(chunks));
+    });
+    return this;
+}
+
+
+// == Decoder stream =======================================================
+function IconvLiteDecoderStream(conv, options) {
+    this.conv = conv;
+    options = options || {};
+    options.encoding = this.encoding = 'utf8'; // We output strings.
+    Transform.call(this, options);
+}
+
+IconvLiteDecoderStream.prototype = Object.create(Transform.prototype, {
+    constructor: { value: IconvLiteDecoderStream }
+});
+
+IconvLiteDecoderStream.prototype._transform = function(chunk, encoding, done) {
+    if (!Buffer.isBuffer(chunk))
+        return done(new Error("Iconv decoding stream needs buffers as its input."));
+    try {
+        var res = this.conv.write(chunk);
+        if (res && res.length) this.push(res, this.encoding);
+        done();
+    }
+    catch (e) {
+        done(e);
+    }
+}
+
+IconvLiteDecoderStream.prototype._flush = function(done) {
+    try {
+        var res = this.conv.end();
+        if (res && res.length) this.push(res, this.encoding);                
+        done();
+    }
+    catch (e) {
+        done(e);
+    }
+}
+
+IconvLiteDecoderStream.prototype.collect = function(cb) {
+    var res = '';
+    this.on('error', cb);
+    this.on('data', function(chunk) { res += chunk; });
+    this.on('end', function() {
+        cb(null, res);
+    });
+    return this;
+}
+