clip-search: fmt + clippy clamp + test AppState arg

Pulls cargo fmt + clippy pass over the new files only — pre-existing
files left untouched even though fmt has drift on them. clamp(1,200)
swaps a manual min/max chain that clippy flagged. test AppState
constructor needed ClipClient::new(None) so the lib-test target
compiles.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/clip_watch.rs

@@ -142,10 +142,7 @@ async fn process_one(
             let emb_bytes = match resp.decode_embedding() {
                 Ok(b) => b,
                 Err(e) => {
-                    warn!(
-                        "clip_watch: bad embedding for {}: {:?}",
-                        cand.rel_path, e
-                    );
+                    warn!("clip_watch: bad embedding for {}: {:?}", cand.rel_path, e);
                     return;
                 }
             };