feat: doctor-cmd implementation

rust/crates/rusty-claude-cli/src/main.rs

@@ -9986,7 +9986,7 @@ UU conflicted.rs",
     }
 
     #[test]
-    fn parse_history_count_defaults_to_ten_when_missing() {
+    fn parse_history_count_defaults_to_twenty_when_missing() {
         // given
         let raw: Option<&str> = None;
 
@@ -9994,7 +9994,7 @@ UU conflicted.rs",
         let parsed = parse_history_count(raw);
 
         // then
-        assert_eq!(parsed, Ok(10));
+        assert_eq!(parsed, Ok(20));
     }
 
     #[test]