The tab testID was reading from tabId, which intentionally stays as the
draft id after a draft -> agent handoff so the panel React key remains
stable and the component does not remount. The data-testid was riding
along on that identity and stayed workspace-tab-draft_xxx forever, even
though the tab semantically became an agent. Tests that look for
workspace-tab-agent_* timed out.
Read testIDs from tab.target via buildDeterministicWorkspaceTabId so the
testID reflects what the tab represents. React key is unchanged.
Mohamed Boudra
81407c5ffc