feat: unify execution and add workspace file imports

Remove Ask/Execute modes and general product tool approvals so requests use the selected runtime, enabled capabilities, and execution account permissions. Migrate retired application metadata while preserving user content.

Retire the Results page while retaining conversation images and stored artifacts. Add local and remote workspace file imports, timestamps and sorting, improve image discovery and saving, and refine workspace navigation and supervision responsiveness. Include the accompanying web-search changes, tests, probes, and product documentation.

Remote imports require an updated Agent. Existing artifacts are not automatically copied into project directories. Validation evidence and outstanding failures remain documented in feature progress files; no full test suite or real-model calls were rerun for this commit.

Release note: Run requests without switching work modes, import files into a selected local or remote workspace folder, sort workspace files by date, and keep using conversation images after removal of the Results page.

docs/features/desktop-pet/logic-design.md

@@ -11,15 +11,15 @@
 | User Stories | [桌面宠物 User Stories](./user-stories.md) |
 | 任务模型 | [Task 与 Job 统一领域模型](../task-and-job/task-and-job-model.md) |
 
-本文负责桌面宠物自身的状态、不变量和决策规则，不重新定义 Task、Conversation、Ask/
-Execute 或附件的既有语义；这些语义以各自权威文档为准。
+本文负责桌面宠物自身的状态、不变量和决策规则，不重新定义 Task、Conversation、工具执行
+或附件的既有语义；这些语义以各自权威文档为准。
 
 ## 1. 核心不变量
 
 ### INV-1 宠物不是第二条执行通道
 
 快速起草和拖放暂存只产生主窗口会话输入区的草稿数据（文本、附件引用），不产生消息、
-不产生 Task、不触发模型调用。发送、模式选择和 Runtime 选择继续完全由主窗口既有流程
+不产生 Task、不触发模型调用。发送和 Runtime 选择继续完全由主窗口既有流程
 拥有。
 
 ### INV-2 状态镜面是既有状态的投影