New revision of the Assistant Panel (#10870)

This is a crate only addition of a new version of the AssistantPanel.
We'll be putting this behind a feature flag while we iron out the new
experience.

Release Notes:

- N/A

---------

Co-authored-by: Nathan Sobo <nathan@zed.dev>
Co-authored-by: Antonio Scandurra <me@as-cii.com>
Co-authored-by: Conrad Irwin <conrad@zed.dev>
Co-authored-by: Marshall Bowers <elliott.codes@gmail.com>
Co-authored-by: Antonio Scandurra <antonio@zed.dev>
Co-authored-by: Nate Butler <nate@zed.dev>
Co-authored-by: Nate Butler <iamnbutler@gmail.com>
Co-authored-by: Max Brunsfeld <maxbrunsfeld@gmail.com>
Co-authored-by: Max <max@zed.dev>

crates/collab_ui/src/notifications/incoming_call_notification.rs

@@ -125,7 +125,7 @@ impl Render for IncomingCallNotification {
 
         cx.set_rem_size(ui_font_size);
 
-        div().size_full().font(ui_font).child(
+        div().size_full().font_family(ui_font).child(
             CollabNotification::new(
                 self.state.call.calling_user.avatar_uri.clone(),
                 Button::new("accept", "Accept").on_click({

crates/collab_ui/src/notifications/project_shared_notification.rs

@@ -129,7 +129,7 @@ impl Render for ProjectSharedNotification {
 
         cx.set_rem_size(ui_font_size);
 
-        div().size_full().font(ui_font).child(
+        div().size_full().font_family(ui_font).child(
             CollabNotification::new(
                 self.owner.avatar_uri.clone(),
                 Button::new("open", "Open").on_click(cx.listener(move |this, _event, cx| {