trello.listWorkspaces lists Workspaces the connected member can access.
automations/list-trello-workspaces.automation.ts
filter accepts "all", "members", "none", or "public" and defaults to "all". "members" selects private Workspaces where the connected user is a member, while "public" selects public Workspaces. Optional second argument { account } selects a Trello binding.
Returns Signal<TrelloWorkspace[]>. Each Workspace has id, name, displayName, nullable lastActivityAt, url, and website.