Fix a bunch of other low-hanging style lints (#36498)

- **Fix a bunch of low hanging style lints like unnecessary-return**
- **Fix single worktree violation**
- **And the rest**

Release Notes:

- N/A

crates/workspace/src/workspace.rs

@@ -1804,7 +1804,7 @@ impl Workspace {
                             .max_by(|b1, b2| b1.worktree_id.cmp(&b2.worktree_id))
                     });
 
-                latest_project_path_opened.map_or(true, |path| path == history_path)
+                latest_project_path_opened.is_none_or(|path| path == history_path)
             })
     }
 
@@ -2284,7 +2284,7 @@ impl Workspace {
             // the current session.
             if close_intent != CloseIntent::Quit
                 && !save_last_workspace
-                && save_result.as_ref().map_or(false, |&res| res)
+                && save_result.as_ref().is_ok_and(|&res| res)
             {
                 this.update_in(cx, |this, window, cx| this.remove_from_session(window, cx))?
                     .await;
@@ -5133,13 +5133,11 @@ impl Workspace {
         self.panes.retain(|p| p != pane);
         if let Some(focus_on) = focus_on {
             focus_on.update(cx, |pane, cx| window.focus(&pane.focus_handle(cx)));
-        } else {
-            if self.active_pane() == pane {
-                self.panes
-                    .last()
-                    .unwrap()
-                    .update(cx, |pane, cx| window.focus(&pane.focus_handle(cx)));
-            }
+        } else if self.active_pane() == pane {
+            self.panes
+                .last()
+                .unwrap()
+                .update(cx, |pane, cx| window.focus(&pane.focus_handle(cx)));
         }
         if self.last_active_center_pane == Some(pane.downgrade()) {
             self.last_active_center_pane = None;
@@ -5893,7 +5891,6 @@ impl Workspace {
 
     pub fn cancel(&mut self, _: &menu::Cancel, window: &mut Window, cx: &mut Context<Self>) {
         if cx.stop_active_drag(window) {
-            return;
         } else if let Some((notification_id, _)) = self.notifications.pop() {
             dismiss_app_notification(&notification_id, cx);
         } else {
@@ -6100,7 +6097,7 @@ fn open_items(
                         // here is a directory, it was already opened further above
                         // with a `find_or_create_worktree`.
                         if let Ok(task) = abs_path_task
-                            && task.await.map_or(true, |p| p.is_file())
+                            && task.await.is_none_or(|p| p.is_file())
                         {
                             return Some((
                                 ix,
@@ -6970,7 +6967,7 @@ async fn join_channel_internal(
                     && project.visible_worktrees(cx).any(|tree| {
                         tree.read(cx)
                             .root_entry()
-                            .map_or(false, |entry| entry.is_dir())
+                            .is_some_and(|entry| entry.is_dir())
                     })
                 {
                     Some(workspace.project.clone())
@@ -7900,7 +7897,6 @@ fn join_pane_into_active(
     cx: &mut App,
 ) {
     if pane == active_pane {
-        return;
     } else if pane.read(cx).items_len() == 0 {
         pane.update(cx, |_, cx| {
             cx.emit(pane::Event::Remove {
@@ -9149,11 +9145,11 @@ mod tests {
         workspace.update_in(cx, |workspace, window, cx| {
             workspace.add_item_to_active_pane(Box::new(item.clone()), None, false, window, cx);
         });
-        return item;
+        item
     }
 
     fn split_pane(cx: &mut VisualTestContext, workspace: &Entity<Workspace>) -> Entity<Pane> {
-        return workspace.update_in(cx, |workspace, window, cx| {
+        workspace.update_in(cx, |workspace, window, cx| {
             let new_pane = workspace.split_pane(
                 workspace.active_pane().clone(),
                 SplitDirection::Right,
@@ -9161,7 +9157,7 @@ mod tests {
                 cx,
             );
             new_pane
-        });
+        })
     }
 
     #[gpui::test]