fix(protocol): approval policy never prompt (#11288)

This removes overly directed language about how the model should behave
when it's in `approval_policy=never` mode.

---------

Co-authored-by: Dylan Hurd <dylan.hurd@openai.com>

codex-rs/core/tests/suite/prompt_caching.rs

@@ -551,9 +551,11 @@ async fn override_before_first_turn_emits_environment_context() -> anyhow::Resul
         })
         .collect();
     assert!(
-        permissions_texts
-            .iter()
-            .any(|text| text.contains("`approval_policy` is `never`")),
+        permissions_texts.iter().any(|text| {
+            let lower = text.to_ascii_lowercase();
+            (lower.contains("approval policy") || lower.contains("approval_policy"))
+                && lower.contains("never")
+        }),
         "permissions message should reflect overridden approval policy: {permissions_texts:?}"
     );
 

codex-rs/core/tests/suite/tool_parallelism.rs

@@ -72,7 +72,7 @@ async fn build_codex_with_test_tool(server: &wiremock::MockServer) -> anyhow::Re
 fn assert_parallel_duration(actual: Duration) {
     // Allow headroom for slow CI scheduling; barrier synchronization already enforces overlap.
     assert!(
-        actual < Duration::from_millis(1_200),
+        actual < Duration::from_millis(1_600),
         "expected parallel execution to finish quickly, got {actual:?}"
     );
 }