Function drainFinal

internal/tui/tui_test.go:3337–3342

drainFinal submits a prompt and pumps the whole turn to completion, returning the settled model. Centralises the submit+drain dance the empty-reply tests share.

(t *testing.T, m Model, prompt string)

// TestEmptyReplyNudgeFiresOnceThenSurfaces: if the model stays empty even after
// the re-prompt (e.g. a server that deterministically swallows the call), the
// latch must stop at one retry (no infinite loop) and the failure must be
// surfaced rather than dying silently as before.
func TestEmptyReplyNudgeFiresOnceThenSurfaces(t *testing.T) {
	var round int
	handler := func(w http.ResponseWriter, _ *http.Request) {
		w.Header().Set("Content-Type", "text/event-stream")
		round++
		fmt.Fprintf(w, "data: %s\n\n", `{"choices":[{"delta":{},"finish_reason":"stop"}],"usage":{"completion_tokens":1}}`)