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/supermaven/src/supermaven.rs

@@ -243,7 +243,7 @@ fn find_relevant_completion<'a>(
                 None => continue 'completions,
             };
 
-        if best_completion.map_or(false, |best| best.len() > trimmed_completion.len()) {
+        if best_completion.is_some_and(|best| best.len() > trimmed_completion.len()) {
             continue;
         }