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/development/release-runbook.md

@@ -100,7 +100,7 @@ to a public channel; follow the user's explicit publication instruction.
   production signing secrets, publish installable release artifacts, or modify
   the checked-in public key registry. The Darwin arm64 target uses `macos-15`
   and the same production locks. Native CI checks do not replace real Host
-  installation, Attach, Ask/Execute, and lifecycle validation during development.
+  installation, Attach, mode-free tool execution, and lifecycle validation during development.
 - `.github/workflows/agent-release.yml` is the only production compound Agent
   publication path. It requires an annotated immutable Agent tag, the protected
   `agent-signing` Environment, native x64/arm64 builds, one production