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/http-handler.ts

@@ -49,7 +49,12 @@ export class HttpForwardingHandler extends ForwardingHandler {
       });
     };
     
-    setupSocketHandlers(socket, handleClose, 'http');
+    // Use custom timeout handler that doesn't close the socket
+    setupSocketHandlers(socket, handleClose, () => {
+      // For HTTP, we can be more aggressive with timeouts since connections are shorter
+      // But still don't close immediately - let the connection finish naturally
+      console.warn(`HTTP socket timeout from ${remoteAddress}`);
+    }, 'http');
     
     socket.on('error', (error) => {
       this.emit(ForwardingHandlerEvents.ERROR, {