Don't render "Initialize Repository" button when no worktrees (#26713)

Closes #26676  

Release Notes:

- Fixed the git panel to not show an "Initialize Repositories" button in
empty projects

crates/git_ui/src/git_panel.rs

@@ -3048,7 +3048,9 @@ impl GitPanel {
                             "No Git repositories"
                         },
                     ))
-                    .children(self.active_repository.is_none().then(|| {
+                    .children({
+                        let worktree_count = self.project.read(cx).visible_worktrees(cx).count();
+                        (worktree_count > 0 && self.active_repository.is_none()).then(|| {
                             h_flex().w_full().justify_around().child(
                                 panel_filled_button("Initialize Repository")
                                     .tooltip(Tooltip::for_action_title_in(
@@ -3062,7 +3064,8 @@ impl GitPanel {
                                         })
                                     }),
                             )
-                    }))
+                        })
+                    })
                     .text_ui_sm(cx)
                     .mx_auto()
                     .text_color(Color::Placeholder.color(cx)),