Implement remote MCP server deployment capabilities

- Add HTTP/JSON-RPC server for remote MCP access
- Configure domain and authentication via environment variables
- Create comprehensive remote deployment documentation
- Support both local (stdio) and remote (HTTP) deployment modes
- Add PM2 and Nginx configuration examples
- Update README with remote server instructions

The server can now be deployed on a VM (e.g., Hetzner) and accessed
from Claude Desktop over HTTPS using the configured domain.

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

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

src/utils/auth-middleware.ts

@@ -0,0 +1,49 @@
+import { Request, Response, NextFunction } from 'express';
+import { logger } from './logger';
+
+/**
+ * Express middleware for authenticating requests with Bearer tokens
+ */
+export function authenticateRequest(authToken?: string) {
+  return (req: Request, res: Response, next: NextFunction): void => {
+    if (!authToken) {
+      // No auth required
+      return next();
+    }
+
+    const authHeader = req.headers['authorization'];
+    
+    if (!authHeader) {
+      logger.warn('Missing authorization header', {
+        ip: req.ip,
+        path: req.path,
+      });
+      
+      res.status(401).json({
+        error: 'Unauthorized',
+        message: 'Missing authorization header',
+      });
+      return;
+    }
+
+    // Support both "Bearer TOKEN" and just "TOKEN" formats
+    const providedToken = authHeader.startsWith('Bearer ') 
+      ? authHeader.substring(7) 
+      : authHeader;
+    
+    if (providedToken !== authToken) {
+      logger.warn('Invalid authentication token', {
+        ip: req.ip,
+        path: req.path,
+      });
+      
+      res.status(401).json({
+        error: 'Unauthorized',
+        message: 'Invalid authentication token',
+      });
+      return;
+    }
+
+    next();
+  };
+}