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/remote-host/README.md

@@ -1,7 +1,7 @@
 # 远程主机与远程执行
 
 本功能负责 SSH Host 管理、Host Key、远程环境安装、GoodBuddy Agent、签名 Runtime、
-远程 Workspace 和 Ask/Execute 生产路径。
+远程 Workspace 和无模式工具执行生产路径。
 
 2026-09-28 新增待实现方向：主机管理迁入应用中心，与“云环境管理”成为同级应用；
 云平台发现已有实例，接入执行时复用 SSH 主机。产品范围见 [PRD](./prd.md)。