Fix fuzzy matching after removing root dirname from stored paths

Co-Authored-By: Nathan Sobo <nathan@zed.dev>

zed/src/worktree/char_bag.rs

@@ -1,4 +1,4 @@
-#[derive(Copy, Clone, Debug)]
+#[derive(Copy, Clone, Debug, Default)]
 pub struct CharBag(u64);
 
 impl CharBag {
@@ -23,6 +23,14 @@ impl CharBag {
     }
 }
 
+impl Extend<char> for CharBag {
+    fn extend<T: IntoIterator<Item = char>>(&mut self, iter: T) {
+        for c in iter {
+            self.insert(c);
+        }
+    }
+}
+
 impl From<&str> for CharBag {
     fn from(s: &str) -> Self {
         let mut bag = Self(0);