fix some tests and prepare next step of evolution

test/test.keepalive-support.node.ts

@@ -18,7 +18,7 @@ tap.test('keepalive support - verify keepalive connections are properly handled'
       }
     });
     
-    socket.on('error', (err) => {
+    socket.on('error', (err: NodeJS.ErrnoException) => {
       // Ignore errors from backend sockets
       console.log(`Backend socket error (expected during cleanup): ${err.code}`);
     });
@@ -56,7 +56,7 @@ tap.test('keepalive support - verify keepalive connections are properly handled'
   const client1 = net.connect(8590, 'localhost');
   
   // Add error handler to prevent unhandled errors
-  client1.on('error', (err) => {
+  client1.on('error', (err: NodeJS.ErrnoException) => {
     console.log(`Client1 error (expected during cleanup): ${err.code}`);
   });
   
@@ -133,7 +133,7 @@ tap.test('keepalive support - verify keepalive connections are properly handled'
   const client2 = net.connect(8591, 'localhost');
   
   // Add error handler to prevent unhandled errors
-  client2.on('error', (err) => {
+  client2.on('error', (err: NodeJS.ErrnoException) => {
     console.log(`Client2 error (expected during cleanup): ${err.code}`);
   });
   
@@ -193,7 +193,7 @@ tap.test('keepalive support - verify keepalive connections are properly handled'
   const client3 = net.connect(8592, 'localhost');
   
   // Add error handler to prevent unhandled errors
-  client3.on('error', (err) => {
+  client3.on('error', (err: NodeJS.ErrnoException) => {
     console.log(`Client3 error (expected during cleanup): ${err.code}`);
   });