chore: rename unless-allow-listed to untrusted (#1378)

For the `approval_policy` config option, renames `unless-allow-listed`
to `untrusted`. In general, when it comes to exec'ing commands, I think
"trusted" is a more accurate term than "safe."

Also drops the `AskForApproval::AutoEdit` variant, as we were not really
making use of it, anyway.

Fixes https://github.com/openai/codex/issues/1250.


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* #1379
* __->__ #1378

codex-rs/core/src/safety.rs

@@ -31,7 +31,7 @@ pub fn assess_patch_safety(
     }
 
     match policy {
-        AskForApproval::OnFailure | AskForApproval::AutoEdit | AskForApproval::Never => {
+        AskForApproval::OnFailure | AskForApproval::Never => {
             // Continue to see if this can be auto-approved.
         }
         // TODO(ragona): I'm not sure this is actually correct? I believe in this case