Add relay server for remote HTTPS access

Node.js/TypeScript relay server that enables remote access to MacroPad:
- WebSocket-based communication between desktop and relay
- Password authentication with bcrypt hashing
- Session management with consistent IDs
- REST API proxying to desktop app
- Web client WebSocket relay
- Login page and PWA-ready app page
- Designed for cloud-node-container deployment

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

macropad-relay/src/server.ts

@@ -0,0 +1,124 @@
+// Express + WebSocket Server Setup
+
+import express from 'express';
+import fs from 'fs';
+import http from 'http';
+import WebSocket, { WebSocketServer } from 'ws';
+import cors from 'cors';
+import helmet from 'helmet';
+import rateLimit from 'express-rate-limit';
+import path from 'path';
+
+import { config } from './config';
+import { logger } from './utils/logger';
+import { SessionManager } from './services/SessionManager';
+import { ConnectionManager } from './services/ConnectionManager';
+import { handleDesktopConnection } from './handlers/desktopHandler';
+import { handleWebClientConnection } from './handlers/webClientHandler';
+import { createApiProxy } from './handlers/apiProxy';
+
+export function createServer() {
+  const app = express();
+  const server = http.createServer(app);
+
+  // Initialize managers
+  const sessionManager = new SessionManager();
+  const connectionManager = new ConnectionManager();
+
+  // Middleware
+  app.use(helmet({
+    contentSecurityPolicy: false // Allow inline scripts for login page
+  }));
+  app.use(cors());
+  app.use(express.json());
+
+  // Rate limiting
+  const limiter = rateLimit({
+    windowMs: config.rateLimitWindowMs,
+    max: config.rateLimitMax,
+    message: { error: 'Too many requests, please try again later' }
+  });
+  app.use(limiter);
+
+  // Static files - check both locations (dev vs production)
+  const publicPath = fs.existsSync(path.join(__dirname, 'public'))
+    ? path.join(__dirname, 'public')
+    : path.join(__dirname, '..', 'public');
+  app.use('/static', express.static(publicPath));
+
+  // Health check
+  app.get('/health', (req, res) => {
+    const stats = connectionManager.getStats();
+    res.json({
+      status: 'ok',
+      ...stats
+    });
+  });
+
+  // Login page for session
+  app.get('/:sessionId', (req, res) => {
+    const session = sessionManager.getSession(req.params.sessionId);
+    if (!session) {
+      return res.status(404).send('Session not found');
+    }
+    res.sendFile(path.join(publicPath, 'login.html'));
+  });
+
+  // PWA app page (after authentication)
+  app.get('/:sessionId/app', (req, res) => {
+    const session = sessionManager.getSession(req.params.sessionId);
+    if (!session) {
+      return res.status(404).send('Session not found');
+    }
+    res.sendFile(path.join(publicPath, 'app.html'));
+  });
+
+  // API proxy routes
+  const apiProxy = createApiProxy(connectionManager, sessionManager);
+  app.all('/:sessionId/api/*', apiProxy);
+
+  // WebSocket server
+  const wss = new WebSocketServer({ noServer: true });
+
+  // Handle HTTP upgrade for WebSocket
+  server.on('upgrade', (request, socket, head) => {
+    const url = new URL(request.url || '', `http://${request.headers.host}`);
+    const pathname = url.pathname;
+
+    // Desktop connection: /desktop
+    if (pathname === '/desktop') {
+      wss.handleUpgrade(request, socket, head, (ws) => {
+        handleDesktopConnection(ws, connectionManager, sessionManager);
+      });
+      return;
+    }
+
+    // Web client connection: /:sessionId/ws
+    const webClientMatch = pathname.match(/^\/([a-zA-Z0-9]+)\/ws$/);
+    if (webClientMatch) {
+      const sessionId = webClientMatch[1];
+      wss.handleUpgrade(request, socket, head, (ws) => {
+        handleWebClientConnection(ws, sessionId, connectionManager, sessionManager);
+      });
+      return;
+    }
+
+    // Invalid path
+    socket.destroy();
+  });
+
+  // Graceful shutdown
+  const shutdown = () => {
+    logger.info('Shutting down...');
+    connectionManager.shutdown();
+    server.close(() => {
+      logger.info('Server closed');
+      process.exit(0);
+    });
+  };
+
+  process.on('SIGTERM', shutdown);
+  process.on('SIGINT', shutdown);
+
+  return { app, server, sessionManager, connectionManager };
+}