Resolve saved Daybreak choices for each subagent turn (#60773)

## Why

A subagent can use a different model from its parent, with different supported access programs. Saved Daybreak choices need to resolve against the subagent's model and remain consistent throughout its turn, including compaction.

## What changed

- Resolve saved choices before native subagent turns start, preserving explicit turn overrides and applying saved toggles on later turns.
- Distinguish inherited parent programs from explicit child selections. Adapt inherited Daybreak Blue/Red selections to the child model while retaining the saved choice as the default for later turns and nested subagents.
- Validate the account associated with automatic selections and reject incompatible saved choices before sending model requests, while retaining rejected user input in conversation history.
- Require model changes to wait until the next turn when a saved Daybreak choice is present.

## Testing

Add coverage for both multi-agent spawn versions, model-specific selection, automatic compaction, WebSocket response reuse, account changes, unsupported choices, and rejected-input persistence across resume.

GitOrigin-RevId: 11971138d656600d9878187225e4d33217e68ad4

codex-rs/core/src/session/step_activation.rs

@@ -269,6 +269,20 @@ impl Session {
         let Some((turn_context, task_done, current)) = target else {
             return TurnSettingsUpdateOutcome::TargetUnavailable;
         };
+        if update
+            .model
+            .as_ref()
+            .is_some_and(|model| *model != current.model_info.slug)
+            && turn_context
+                .extension_data
+                .get::<crate::agent::helper_daybreak::SavedIntent>()
+                .is_some()
+        {
+            return TurnSettingsUpdateOutcome::Rejected {
+                reason: "Change the model on the next turn when using a saved Daybreak choice"
+                    .to_string(),
+            };
+        }
         let TurnSettingsUpdate {
             approvals_reviewer,
             environments: environment_requests,

codex-rs/core/src/session/turn_context.rs

@@ -1491,7 +1491,7 @@ impl Session {
         turn_context.cyber_access_program =
             cyber_access_program::for_provider(&turn_context.config, options.cyber_access_program);
         if let Some(admission) = options.helper_admission {
-            admission.capture_intent(self, &turn_context).await;
+            admission.capture_intent(self, &mut turn_context).await;
         }
         // Tool observers retain this turn's selection even after a later turn starts.
         if let Some(program) = turn_context.cyber_access_program {