fix: update default port values and app target configuration

Change default port values from empty strings to 0 in InstanceDetail form
Update APP_TARGET in vite config to use local network IP for development

src/views/InstanceDetail.vue

@@ -521,8 +521,8 @@ export default {
                 name: '',
                 type: '',
                 localIP: '',
-                localPort: '',
-                remotePort: '',
+                localPort: 0,
+                remotePort: 0,
                 auth_method: formData.value.auth_method,
                 serverAddr: formData.value.serverAddr,
                 serverPort: formData.value.serverPort,
@@ -599,8 +599,8 @@ export default {
                     name: formData.value.name,
                     type: formData.value.type,
                     localIP: formData.value.localIP,
-                    localPort: formData.value.localPort.toString(),
-                    remotePort: formData.value.remotePort.toString()
+                    localPort: formData.value.localPort,
+                    remotePort: formData.value.remotePort
                 };
                 
                 if (isEditProxy.value) {