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/config.ts

@@ -0,0 +1,35 @@
+// Configuration for MacroPad Relay Server
+
+import dotenv from 'dotenv';
+import path from 'path';
+
+dotenv.config();
+
+export const config = {
+  port: parseInt(process.env.PORT || '3000', 10),
+  host: process.env.HOST || '0.0.0.0',
+
+  // Data storage
+  dataDir: process.env.DATA_DIR || path.join(__dirname, '..', 'data'),
+
+  // Session settings
+  sessionIdLength: parseInt(process.env.SESSION_ID_LENGTH || '6', 10),
+
+  // Security
+  bcryptRounds: parseInt(process.env.BCRYPT_ROUNDS || '10', 10),
+
+  // Rate limiting
+  rateLimitWindowMs: parseInt(process.env.RATE_LIMIT_WINDOW_MS || '900000', 10), // 15 minutes
+  rateLimitMax: parseInt(process.env.RATE_LIMIT_MAX || '100', 10),
+
+  // WebSocket
+  pingInterval: parseInt(process.env.PING_INTERVAL || '30000', 10), // 30 seconds
+  requestTimeout: parseInt(process.env.REQUEST_TIMEOUT || '30000', 10), // 30 seconds
+
+  // Logging
+  logLevel: process.env.LOG_LEVEL || 'info',
+
+  // Environment
+  nodeEnv: process.env.NODE_ENV || 'development',
+  isDevelopment: process.env.NODE_ENV !== 'production',
+};