Show error and warning indicators in tabs (#21383)

Closes #21179

Release Notes:

- Add setting to display error and warning indicators in tabs.

<img width="454" alt="demo_with_icons"
src="https://github.com/user-attachments/assets/6002b4d4-dca8-4e2a-842d-1df3e281fcd2">
<img width="454" alt="demo_without_icons"
src="https://github.com/user-attachments/assets/df4b67bd-1a6c-4354-847e-d7fea95c1b7e">

crates/workspace/Cargo.toml

@@ -38,7 +38,6 @@ db.workspace = true
 derive_more.workspace = true
 fs.workspace = true
 futures.workspace = true
-git.workspace = true
 gpui.workspace = true
 http_client.workspace = true
 itertools.workspace = true