VS Code extension: assistant's text reply is hidden when the turn ends with ExitPlanMode (plan approval card)

Environment: Claude Code VS Code native extension on Windows + WSL2 Ubuntu; plan mode; model claude-fable-5.

Repro: In plan mode, the user asks a question. Claude answers in prose, then calls ExitPlanMode in the same turn (as plan-mode instructions require — turns must end with ExitPlanMode). In the transcript UI, the prose answer is not rendered: the user sees only collapsed "Thinking" blocks followed by the "Claude's Plan" card. Screenshot available on request.

Expected: the assistant's text message renders in the conversation before the plan-approval card.

Actual: the text is swallowed; the user asked the same question 3 times, believing Claude was ignoring them. The only workaround was for Claude to end the turn WITHOUT calling ExitPlanMode — which violates the plan-mode contract.

Impact: any plan-mode Q&A exchange looks like Claude ignoring the user; erodes trust and forces protocol violations to communicate.