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/utils/idGenerator.ts

@@ -0,0 +1,31 @@
+// Unique ID generation utilities
+
+import { randomBytes } from 'crypto';
+
+const BASE62_CHARS = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789';
+
+/**
+ * Generate a random base62 string of specified length.
+ * Uses cryptographically secure random bytes.
+ */
+export function generateSessionId(length: number = 6): string {
+  const bytes = randomBytes(length);
+  let result = '';
+
+  for (let i = 0; i < length; i++) {
+    result += BASE62_CHARS[bytes[i] % BASE62_CHARS.length];
+  }
+
+  return result;
+}
+
+/**
+ * Generate a UUID v4 for request IDs.
+ */
+export function generateRequestId(): string {
+  return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, (c) => {
+    const r = Math.random() * 16 | 0;
+    const v = c === 'x' ? r : (r & 0x3 | 0x8);
+    return v.toString(16);
+  });
+}

macropad-relay/src/utils/logger.ts

@@ -0,0 +1,36 @@
+// Logger utility using Winston
+
+import winston from 'winston';
+import { config } from '../config';
+
+const logFormat = winston.format.combine(
+  winston.format.timestamp({ format: 'YYYY-MM-DD HH:mm:ss' }),
+  winston.format.errors({ stack: true }),
+  winston.format.printf(({ level, message, timestamp, stack }) => {
+    return `${timestamp} [${level.toUpperCase()}]: ${stack || message}`;
+  })
+);
+
+export const logger = winston.createLogger({
+  level: config.logLevel,
+  format: logFormat,
+  transports: [
+    new winston.transports.Console({
+      format: winston.format.combine(
+        winston.format.colorize(),
+        logFormat
+      )
+    })
+  ]
+});
+
+// Add file transport in production
+if (!config.isDevelopment) {
+  logger.add(new winston.transports.File({
+    filename: 'error.log',
+    level: 'error'
+  }));
+  logger.add(new winston.transports.File({
+    filename: 'combined.log'
+  }));
+}