new path picker (#11015)

Still TODO:

* Disable the new save-as for local projects
* Wire up sending the new path to the remote server

Release Notes:

- Added the ability to "Save-as" in remote projects

---------

Co-authored-by: Nathan <nathan@zed.dev>
Co-authored-by: Bennet <bennetbo@gmx.de>

crates/project/src/project_tests.rs

@@ -2942,7 +2942,12 @@ async fn test_save_as(cx: &mut gpui::TestAppContext) {
     });
     project
         .update(cx, |project, cx| {
-            project.save_buffer_as(buffer.clone(), "/dir/file1.rs".into(), cx)
+            let worktree_id = project.worktrees().next().unwrap().read(cx).id();
+            let path = ProjectPath {
+                worktree_id,
+                path: Arc::from(Path::new("file1.rs")),
+            };
+            project.save_buffer_as(buffer.clone(), path, cx)
         })
         .await
         .unwrap();