feat: Refactor server implementation to support Bun and Node environments

- Introduced `ServerNode` and `BunServer` classes to handle server logic for Node and Bun respectively.
- Updated `App` class to initialize the appropriate server based on the runtime environment.
- Enhanced `parseBody` function to handle request body parsing for both environments.
- Modified WebSocket handling to support Bun's WebSocket upgrade mechanism.
- Improved error handling and response structure across the server implementation.
- Added support for custom middleware in the server's request handling.
- Refactored server base functionality into `ServerBase` for better code organization.
- Updated type definitions to reflect changes in server options and listener handling.
- Added a new demo for testing the server functionality with various request types.

src/test/listen-ip.ts

@@ -1,7 +1,7 @@
 // import { Server } from 'node:http';
-import { Server } from '../server/server.ts'
+import { ServerNode } from '../server/server.ts'
 
-const server = new Server({
+const server = new ServerNode({
   path: '/',
   handle: async (data, ctx) => {
     console.log('ctx', ctx.req.url)