合并 origin/master（AGC 统一错误诊断 / 图集连通域切分）

- commands.rs：接入 master 新增的 read_agent_runtime_error_detail 命令，并补上 prepare_local_project_asset_generation 里新增的 slice_mode / grid_x / grid_y 三个字段
- main.rs：注册 read_agent_runtime_error_detail
- 保留我们这边的 read_direct_tool_calls 等命令，两侧新增全部保留
- 冲突原为纯追加，按"两侧语义都保住"处理；未跑测试

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

@@ -4617,6 +4617,9 @@ pub(crate) fn prepare_local_project_asset_generation(
             .unwrap_or_else(|| LOCAL_PROJECT_ASSET_DEFAULT_ASSET_NAME.to_string()),
             replace_existing: false,
             slice_count: None,
+            slice_mode: None,
+            grid_x: None,
+            grid_y: None,
         },
     })
 }
@@ -5264,6 +5267,37 @@ pub(crate) async fn read_direct_project_conversation(
     .map_err(|error| format!("读取 DirectProject 历史后台任务失败：{error}"))?
 }
 
+#[tauri::command]
+pub(crate) async fn read_agent_runtime_error_detail(
+    project_path: String,
+    detail_ref: String,
+) -> Result<String, String> {
+    tauri::async_runtime::spawn_blocking(move || {
+        let root = Path::new(project_path.trim());
+        enforce_project_permission_policy(root, "conversation.read")?;
+        let relative = detail_ref.trim();
+        let Some(file_name) = relative.strip_prefix(".agent/runtime/errors/") else {
+            return Err("错误诊断引用不在项目错误目录内".to_string());
+        };
+        if file_name.is_empty()
+            || file_name.contains(['/', '\\'])
+            || file_name.contains("..")
+            || !file_name.ends_with(".json")
+        {
+            return Err("错误诊断引用格式无效".to_string());
+        }
+        let path = root.join(relative);
+        prepare_game_creator_private_path_for_read(&path, false, "统一错误诊断")?;
+        let bytes = std::fs::read(&path).map_err(|error| format!("读取错误诊断失败：{error}"))?;
+        if bytes.len() > 16 * 1024 {
+            return Err("错误诊断超过读取上限".to_string());
+        }
+        let text = String::from_utf8(bytes).map_err(|_| "错误诊断不是 UTF-8 文本".to_string())?;
+        Ok(redact_agent_runtime_error(root, &text, 16 * 1024))
+    })
+    .await
+    .map_err(|error| format!("读取统一错误诊断后台任务失败：{error}"))?
+}
 #[tauri::command]
 pub(crate) async fn read_direct_tool_calls(
     project_path: String,