fix(codegen): resolve clippy warnings in CRLF handling code

Co-authored-by: Dunqing <29533304+Dunqing@users.noreply.github.com>

Author: Copilot

crates/oxc_codegen/src/comment.rs

@@ -13,9 +13,9 @@ pub type CommentsMap = FxHashMap</* attached_to */ u32, Vec<Comment>>;
 /// This avoids creating empty strings between CR and LF characters.
 ///
 /// # Example
-/// Standard split would turn "line1\r\nline2" into ["line1", "", "line2"] because
+/// Standard split would turn `"line1\r\nline2"` into `["line1", "", "line2"]` because
 /// it treats \r and \n as separate terminators. This iterator correctly produces
-/// ["line1", "line2"] by treating \r\n as a single terminator.
+/// `["line1", "line2"]` by treating \r\n as a single terminator.
 struct LineTerminatorSplitter<'a> {
     text: &'a str,
     position: usize,
@@ -36,9 +36,9 @@ impl<'a> Iterator for LineTerminatorSplitter<'a> {
         }
 
         let start = self.position;
-        let mut chars = self.text[self.position..].char_indices();
+        let chars = self.text[self.position..].char_indices();
 
-        while let Some((i, c)) = chars.next() {
+        for (i, c) in chars {
             if is_line_terminator(c) {
                 let line = &self.text[start..start + i];
                 self.position = start + i + c.len_utf8();