Add repetition detection

src/search/negamax.rs

@@ -24,6 +24,10 @@ pub fn negamax(
         bail!("Time is up! In Negamax");
     }
 
+    if plies != 0 && game.in_repetition() {
+        return Ok(0);
+    }
+
     if depth == 0 {
         let q_score = quiescence(game, alpha, beta, time_info).map_err(|e| anyhow!("{e}"))?;
         return Ok(q_score);