chore: rename AskForApproval::UnlessAllowListed to AskForApproval::UnlessTrusted (#1385)

We could just rename to `Untrusted` instead of `UnlessTrusted`, but I
think `AskForApproval::UnlessTrusted` reads a bit better.

codex-rs/core/src/protocol.rs

@@ -120,7 +120,7 @@ pub enum AskForApproval {
     /// Everything else will ask the user to approve.
     #[default]
     #[serde(rename = "untrusted")]
-    UnlessAllowListed,
+    UnlessTrusted,
 
     /// *All* commands are auto‑approved, but they are expected to run inside a
     /// sandbox where network access is disabled and writes are confined to a