Archive any workspace from the app (#2003)

* feat(app): expose archive for every workspace

Workspace actions now archive one workspace by id. The daemon remains responsible for backing-specific cleanup, including removing a managed worktree only after its final workspace is archived.

* refactor(app): clarify archive descriptor name

* fix(app): preserve workspace archive safety

* fix(app): allow archive without upstream

* refactor(app): remove stale archive callback

* test(app): cover workspace archive ownership

packages/app/src/keyboard/actions.ts

@@ -44,7 +44,7 @@ export type KeyboardActionId =
   | "workspace.terminal.new"
   | "workspace.new"
   | "worktree.new"
-  | "worktree.archive"
+  | "workspace.archive"
   | "view.toggle.focus"
   | "theme.cycle"
   | "message-input.action";