修复重进会话无法恢复运行中的 Direct 回合：Rust 增加活跃回合只读探测

新增 read_direct_codex_active_turn 只读命令：返回当前登记的 { clientTurnId, startedAt }，供前端重进会话时接管正在跑的回合
DirectTaonierActiveInvocation 增加 started_at_ms 登记时刻，供只读探测与后续兜底释放判断这一轮的年龄
不改守卫互斥语义与 Drop 释放时机：探测既不进入也不抢占
把命令注册进 main.rs 的 invoke_handler
新增用例：登记中的回合能被只读探测看到、探测本身不占有不释放、Drop 之后回到 None

apps/ai-game-creator-shell/src-tauri/src/agent/direct_runtime.rs

@@ -263,12 +263,18 @@ fn direct_taonier_regeneration_invocation_sha256(invocation_id: &str) -> String
 #[derive(Debug)]
 struct DirectTaonierActiveInvocation {
     invocation_id: String,
+    /// 登记时刻（Unix 毫秒）。只读探测与"终止"兜底都用它判断这一轮的年龄。
+    started_at_ms: u64,
 }
 
 static DIRECT_TAONIER_ACTIVE_INVOCATIONS: OnceLock<
     Mutex<HashMap<PathBuf, DirectTaonierActiveInvocation>>,
 > = OnceLock::new();
 
+fn direct_taonier_active_now_millis() -> u64 {
+    unix_millis().min(u128::from(u64::MAX)) as u64
+}
+
 #[derive(Debug)]
 pub(crate) struct DirectTaonierActiveInvocationGuard {
     root: PathBuf,
@@ -300,6 +306,7 @@ impl DirectTaonierActiveInvocationGuard {
                     root.clone(),
                     DirectTaonierActiveInvocation {
                         invocation_id: invocation_id.to_string(),
+                        started_at_ms: direct_taonier_active_now_millis(),
                     },
                 );
             }
@@ -345,6 +352,46 @@ pub(crate) fn direct_taonier_active_invocation_id_at(root: &Path) -> Result<Stri
         })
 }
 
+/// `read_direct_codex_active_turn` 的返回值：前端重进会话时用它恢复正在跑的回合。
+#[derive(Clone, Debug, Eq, PartialEq, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub(crate) struct DirectActiveTurnView {
+    /// 与事件 `turnId` 同一个身份（守卫里登记的 `invocation_id`）。
+    pub(crate) client_turn_id: String,
+    /// 这一轮登记的时刻（Unix 毫秒）。
+    pub(crate) started_at: u64,
+}
+
+/// 只读探测：该项目当前登记的 Direct 活跃回合（`None` = 没有回合在跑）。
+///
+/// 只读，不改变互斥语义与释放时机：守卫仍然只由回合自己的 `Drop` 释放。
+pub(crate) fn read_direct_taonier_active_invocation_at(
+    root: &Path,
+) -> Result<Option<DirectActiveTurnView>, String> {
+    let root = root
+        .canonicalize()
+        .map_err(|error| format!("无法锚定 Direct 调用项目目录：{error}"))?;
+    Ok(DIRECT_TAONIER_ACTIVE_INVOCATIONS
+        .get_or_init(|| Mutex::new(HashMap::new()))
+        .lock()
+        .map_err(|_| "Direct 调用身份锁已损坏".to_string())?
+        .get(&root)
+        .map(|active| DirectActiveTurnView {
+            client_turn_id: active.invocation_id.clone(),
+            started_at: active.started_at_ms,
+        }))
+}
+
+/// 只读命令：读取该项目当前登记的 Direct 活跃回合，供前端重进会话时恢复。
+///
+/// 不进入、不抢占、不释放守卫；没有回合时返回 `null`。
+#[tauri::command]
+pub(crate) fn read_direct_codex_active_turn(
+    project_path: String,
+) -> Result<Option<DirectActiveTurnView>, String> {
+    read_direct_taonier_active_invocation_at(Path::new(project_path.trim()))
+}
+
 fn direct_taonier_regeneration_project_id(root: &Path) -> Result<String, String> {
     let project_id = read_manifest(&root.join(".agent/manifest.json"))?
         .project_id
@@ -4771,6 +4818,42 @@ mod tests {
             .expect("lost-response replay after the original turn finishes");
     }
 
+    #[test]
+    fn read_direct_active_turn_reports_the_registered_turn_and_disappears_after_drop() {
+        let root = tempfile::tempdir().expect("active invocation root");
+        assert_eq!(
+            read_direct_taonier_active_invocation_at(root.path()).expect("read idle project"),
+            None
+        );
+
+        let first = DirectTaonierActiveInvocationGuard::enter(root.path(), "client-turn-read-1")
+            .expect("first client turn");
+        let running = read_direct_taonier_active_invocation_at(root.path())
+            .expect("read running project")
+            .expect("running turn is visible to the read-only probe");
+        assert_eq!(running.client_turn_id, "client-turn-read-1");
+        assert!(running.started_at > 0, "{running:?}");
+        // camelCase 契约：前端按 `clientTurnId` / `startedAt` 取值。
+        assert_eq!(
+            serde_json::to_value(&running).expect("serialize view"),
+            serde_json::json!({
+                "clientTurnId": "client-turn-read-1",
+                "startedAt": running.started_at,
+            })
+        );
+        // 只读探测不占有、不释放：探测之后同项目第二次进入仍然被拒。
+        let duplicate =
+            DirectTaonierActiveInvocationGuard::enter(root.path(), "client-turn-read-2")
+                .expect_err("read-only probe must not take over the project");
+        assert!(!duplicate.starts_with(DIRECT_CODEX_TURN_ALREADY_RUNNING_PREFIX));
+
+        drop(first);
+        assert_eq!(
+            read_direct_taonier_active_invocation_at(root.path()).expect("read idle project"),
+            None
+        );
+    }
+
     #[test]
     fn direct_success_reply_is_persisted_once_with_the_stable_client_turn_identity() {
         let root = tempfile::tempdir().expect("temp dir");

apps/ai-game-creator-shell/src-tauri/src/main.rs

@@ -2669,6 +2669,7 @@ fn main() {
             chat_with_game_creator_role_agent,
             chat_with_game_creator_role_agent_stream,
             chat_with_game_creator_direct_codex,
+            read_direct_codex_active_turn,
             cancel_direct_codex_turn,
             select_game_creator_reasoning_effort,
             start_planning_session_v2,