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/direct-model-agent/README.md

@@ -41,11 +41,10 @@ Task、Job、Subjob、Run 和 Subagent 的对象关系以
 - 直连文本模型的普通问答、工具轮次和上下文摘要会在尚无可见输出时，对瞬时网络错误或
   单次请求超时最多自动重试 3 次。
 - OpenCode、Continue 和 DeepSeek Harness 继续使用各自原生执行与委派能力。
-- Ask 可搜索和分页读取工作区，但不允许补丁写入或进程执行；Subagent 若在 Ask 中使用，
-  只能继承 Ask 的只读能力。
+- 正常请求可使用已注册的搜索、读取、补丁与进程工具；Subagent 继承父请求能力范围。
 - 搜索、进程和 Subagent 的长输出返回预览与续读位置，完整内容保留到所属会话或 Runtime 释放。
-  Ask 和 Execute 均可续读当前会话已取得的输出，详见 [输出契约](./technical-design.md#43-输出边界)。
-- Execute 表示用户授权当前执行空间账号的完整能力，不增加第二套工具审批或权限档位。
+  可续读当前会话已取得的输出，详见 [输出契约](./technical-design.md#43-输出边界)。
+- 使用当前执行空间账号权限，不增加第二套工具审批或权限档位。
 - 首版跨平台指桌面本机 Windows、macOS 和 Linux。托管 SSH 项目当前继续使用远端
   OpenCode；未来若向远端直连模型开放本工具，命令必须由 Host Agent 执行，绝不能回退到
   桌面本机。