clippy: zero pedantic warnings across the tree

hive-ag3nt/src/mcp.rs

@@ -308,11 +308,13 @@ where
 /// content failure and the model would burn a turn retrying it.
 pub fn annotate_retries(mut s: String, retries: u32) -> String {
     if retries > 0 {
+        use std::fmt::Write as _;
         let suffix = if retries == 1 { "retry" } else { "retries" };
-        s.push_str(&format!(
+        let _ = write!(
+            s,
             "\n\n(note: hive socket connect needed {retries} {suffix} — c0re likely \
              restarted. Your request did succeed on the final attempt; no action needed.)"
-        ));
+        );
     }
     s
 }