One big cleanup pass of clippy lints

Co-authored-by: Mikayla <mikayla@zed.dev>

crates/text/src/operation_queue.rs

@@ -26,6 +26,12 @@ impl OperationKey {
     }
 }
 
+impl<T: Operation> Default for OperationQueue<T> {
+    fn default() -> Self {
+        OperationQueue::new()
+    }
+}
+
 impl<T: Operation> OperationQueue<T> {
     pub fn new() -> Self {
         OperationQueue(SumTree::new())
@@ -35,6 +41,10 @@ impl<T: Operation> OperationQueue<T> {
         self.0.summary().len
     }
 
+    pub fn is_empty(&self) -> bool {
+        self.len() == 0
+    }
+
     pub fn insert(&mut self, mut ops: Vec<T>) {
         ops.sort_by_key(|op| op.lamport_timestamp());
         ops.dedup_by_key(|op| op.lamport_timestamp());