agent2: Only setup real client for real models (#37403)

Before we were setting up lots of test setup regardless of if we were
actually going to be making real requests or not.

This will hopefully help with intermittent test errors we're seeing on
Windows in CI.

Release Notes:

- N/A

crates/agent2/src/tests/mod.rs

@@ -72,7 +72,6 @@ async fn test_echo(cx: &mut TestAppContext) {
 }
 
 #[gpui::test]
-#[cfg_attr(target_os = "windows", ignore)] // TODO: Fix this test on Windows
 async fn test_thinking(cx: &mut TestAppContext) {
     let ThreadTest { model, thread, .. } = setup(cx, TestModel::Fake).await;
     let fake_model = model.as_fake();
@@ -1349,7 +1348,6 @@ async fn test_cancellation(cx: &mut TestAppContext) {
 }
 
 #[gpui::test]
-#[cfg_attr(target_os = "windows", ignore)] // TODO: Fix this test on Windows
 async fn test_in_progress_send_canceled_by_next_send(cx: &mut TestAppContext) {
     let ThreadTest { model, thread, .. } = setup(cx, TestModel::Fake).await;
     let fake_model = model.as_fake();
@@ -1688,7 +1686,6 @@ async fn test_truncate_second_message(cx: &mut TestAppContext) {
 }
 
 #[gpui::test]
-#[cfg_attr(target_os = "windows", ignore)] // TODO: Fix this test on Windows
 async fn test_title_generation(cx: &mut TestAppContext) {
     let ThreadTest { model, thread, .. } = setup(cx, TestModel::Fake).await;
     let fake_model = model.as_fake();
@@ -2353,15 +2350,20 @@ async fn setup(cx: &mut TestAppContext, model: TestModel) -> ThreadTest {
         settings::init(cx);
         Project::init_settings(cx);
         agent_settings::init(cx);
-        gpui_tokio::init(cx);
-        let http_client = ReqwestClient::user_agent("agent tests").unwrap();
-        cx.set_http_client(Arc::new(http_client));
 
-        client::init_settings(cx);
-        let client = Client::production(cx);
-        let user_store = cx.new(|cx| UserStore::new(client.clone(), cx));
-        language_model::init(client.clone(), cx);
-        language_models::init(user_store, client.clone(), cx);
+        match model {
+            TestModel::Fake => {}
+            TestModel::Sonnet4 => {
+                gpui_tokio::init(cx);
+                let http_client = ReqwestClient::user_agent("agent tests").unwrap();
+                cx.set_http_client(Arc::new(http_client));
+                client::init_settings(cx);
+                let client = Client::production(cx);
+                let user_store = cx.new(|cx| UserStore::new(client.clone(), cx));
+                language_model::init(client.clone(), cx);
+                language_models::init(user_store, client.clone(), cx);
+            }
+        };
 
         watch_settings(fs.clone(), cx);
     });