clippy: zero pedantic warnings across the tree

hive-c0re/src/agent_server.rs

@@ -376,7 +376,11 @@ mod tests {
     fn auto_reminder_path_format() {
         let p = auto_reminder_path("damocles");
         assert!(p.starts_with("/agents/damocles/state/reminders/auto-"));
-        assert!(p.ends_with(".md"));
+        assert!(
+            std::path::Path::new(&p)
+                .extension()
+                .is_some_and(|ext| ext.eq_ignore_ascii_case("md"))
+        );
     }
 
     #[test]