eval: Add eval unit tests as a CI job (#32152)

We run the unit evals once a day in the middle of the night, and trigger
a Slack post if it fails.


Release Notes:

- N/A

---------

Co-authored-by: Oleksiy Syvokon <oleksiy.syvokon@gmail.com>

crates/assistant_tools/src/edit_agent/evals.rs

@@ -1351,7 +1351,7 @@ fn eval(iterations: usize, expected_pass_ratio: f32, mut eval: EvalInput) {
 
     let mismatched_tag_ratio =
         cumulative_parser_metrics.mismatched_tags as f32 / cumulative_parser_metrics.tags as f32;
-    if mismatched_tag_ratio > 0.05 {
+    if mismatched_tag_ratio > 0.10 {
         for eval_output in eval_outputs {
             println!("{}", eval_output);
         }