Enhance socket cleanup and management for improved connection handling

- Refactor cleanupSocket function to support options for immediate destruction, allowing drain, and grace periods.
- Introduce createIndependentSocketHandlers for better management of half-open connections between client and server sockets.
- Update various handlers (HTTP, HTTPS passthrough, HTTPS terminate) to utilize new cleanup and socket management functions.
- Implement custom timeout handling in socket setup to prevent immediate closure during keep-alive connections.
- Add tests for long-lived connections and half-open connection scenarios to ensure stability and reliability.
- Adjust connection manager to handle socket cleanup based on activity status, improving resource management.

ts/forwarding/handlers/https-terminate-to-http-handler.ts

@@ -112,7 +112,7 @@ export class HttpsTerminateToHttpHandler extends ForwardingHandler {
     });
     
     // Set up error handling with our cleanup utility
-    setupSocketHandlers(tlsSocket, handleClose, 'tls');
+    setupSocketHandlers(tlsSocket, handleClose, undefined, 'tls');
     
     // Set timeout
     const timeout = this.getTimeout();
@@ -167,7 +167,7 @@ export class HttpsTerminateToHttpHandler extends ForwardingHandler {
         });
         
         // Set up handlers for backend socket
-        setupSocketHandlers(backendSocket, newHandleClose, 'backend');
+        setupSocketHandlers(backendSocket, newHandleClose, undefined, 'backend');
         
         backendSocket.on('error', (error) => {
           this.emit(ForwardingHandlerEvents.ERROR, {