listWorkspaces discovers the workspace GIDs required by project and task actions.
automations/list-asana-workspaces.automation.ts
limit is 1–100 and defaults to 100; optional offset is the opaque token from the previous result; optional account defaults to the project binding.
Returns Signal<{ workspaces: AsanaWorkspace[]; pageInfo: { nextOffset?: string } }>; workspaces include id, name/type, emailDomains, and isOrganization.