Capture saved Daybreak preferences for native helpers (#60749)

## What changed

Add the disabled-by-default `daybreak_program_propagation` feature to capture a parent's saved Daybreak choice when spawning native helpers. Retain the choice and account identity for helper turns and nested spawns, while preserving explicit `cyber_access_program` overrides. A helper's own saved preference takes precedence on later turns.

Read pending metadata before persisted metadata so preferences survive thread materialization, with stored choices taking precedence. Share this resolution logic with `thread/read` and support refreshing the feature through user configuration.

## Testing

Add coverage for saved and pending preferences, unset choices, explicit overrides, failed metadata reads, nested spawns, parent unloading, feature withdrawal, and preference changes between helper turns.

GitOrigin-RevId: b3b349da8cb3d48154cddf058890587385efcda2

codex-rs/thread-store/src/error.rs

@@ -81,6 +81,24 @@ pub enum ThreadStoreError {
     },
 }
 
+impl ThreadStoreError {
+    /// Whether a read found no persisted record for this specific thread.
+    pub fn is_missing_for_read(&self, requested_thread_id: ThreadId) -> bool {
+        match self {
+            Self::ThreadNotFound { thread_id } => *thread_id == requested_thread_id,
+            // The local store's strict read uses this legacy error for an unmaterialized rollout.
+            Self::InvalidRequest { message } => {
+                message == &format!("no rollout found for thread id {requested_thread_id}")
+            }
+            Self::Conflict { .. }
+            | Self::Unsupported { .. }
+            | Self::Retryable { .. }
+            | Self::OutcomeUnknown { .. }
+            | Self::Internal { .. } => false,
+        }
+    }
+}
+
 #[cfg(test)]
 #[path = "error_tests.rs"]
 mod tests;