Start separating authentication from connection to collab (#35471)

This pull request should be idempotent, but lays the groundwork for
avoiding to connect to collab in order to interact with AI features
provided by Zed.

Release Notes:

- N/A

---------

Co-authored-by: Marshall Bowers <git@maxdeviant.com>
Co-authored-by: Richard Feldman <oss@rtfeldman.com>

crates/collab_ui/src/collab_panel.rs

@@ -2331,7 +2331,7 @@ impl CollabPanel {
                                 let client = this.client.clone();
                                 cx.spawn_in(window, async move |_, cx| {
                                     client
-                                        .authenticate_and_connect(true, &cx)
+                                        .connect(true, &cx)
                                         .await
                                         .into_response()
                                         .notify_async_err(cx);