允许损坏策划会话降级打开项目

会话读取失败时保留工作台与产物访问能力

新增策划会话备份重置命令，不删除工作区产物

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

@@ -845,6 +845,24 @@ pub(crate) fn hydrate_design_agent_session(
     Ok(Some(design_view(&session, active.is_none())))
 }
 
+#[tauri::command]
+pub(crate) fn reset_design_agent_session(project_path: String) -> Result<(), String> {
+    let root = Path::new(project_path.trim());
+    enforce_project_permission_policy(root, "conversation.write")?;
+    design_project_id(root)?;
+    let _lock = acquire_game_creator_agent_runtime_project_write_lock_with_wait(
+        root,
+        "design.session-reset",
+    )?;
+    let path = crate::agent::runtime_protocol::design_session_path(root);
+    if path.exists() {
+        let backup = path.with_file_name(format!("session.corrupted.{}.json", unix_timestamp()));
+        std::fs::rename(&path, &backup)
+            .map_err(|error| format!("备份损坏的策划会话失败：{error}"))?;
+    }
+    Ok(())
+}
+
 #[tauri::command]
 pub(crate) fn get_design_agent_runtime_mode(
     project_path: String,

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

@@ -2583,6 +2583,7 @@ fn main() {
             decide_planning_artifact_v2,
             hydrate_planning_session_v2,
             hydrate_design_agent_session,
+            reset_design_agent_session,
             get_design_agent_runtime_mode,
             set_design_agent_runtime_mode,
             debug_fast_forward_design_session,

apps/ai-game-creator-shell/src/App.tsx

@@ -3117,7 +3117,9 @@ export function App({
           }
         } catch (error) {
           if (planningStartMode) {
-            throw error;
+            setPlanGddError(
+              `策划会话无法恢复：${error instanceof Error ? error.message : String(error)}`,
+            );
           }
         }
         try {