fix(app-server): mark thread/turns/list and exclude_turns as experime… (#20499)

…ntal

We have some bugs to work out and it is not quite ready to consume as a
public API.

codex-rs/app-server-protocol/src/protocol/common.rs

@@ -564,6 +564,7 @@ client_request_definitions! {
         serialization: thread_id(params.thread_id),
         response: v2::ThreadReadResponse,
     },
+    #[experimental("thread/turns/list")]
     ThreadTurnsList => "thread/turns/list" {
         params: v2::ThreadTurnsListParams,
         // Explicitly concurrent: this primarily reads append-only rollout storage.

codex-rs/app-server-protocol/src/protocol/v2.rs

@@ -3738,6 +3738,7 @@ pub struct ThreadResumeParams {
     /// When true, return only thread metadata and live-resume state without
     /// populating `thread.turns`. This is useful when the client plans to call
     /// `thread/turns/list` immediately after resuming.
+    #[experimental("thread/resume.excludeTurns")]
     #[serde(default, skip_serializing_if = "std::ops::Not::not")]
     pub exclude_turns: bool,
     /// If true, persist additional rollout EventMsg variants required to
@@ -3842,6 +3843,7 @@ pub struct ThreadForkParams {
     /// When true, return only thread metadata and live fork state without
     /// populating `thread.turns`. This is useful when the client plans to call
     /// `thread/turns/list` immediately after forking.
+    #[experimental("thread/fork.excludeTurns")]
     #[serde(default, skip_serializing_if = "std::ops::Not::not")]
     pub exclude_turns: bool,
     /// If true, persist additional rollout EventMsg variants required to