feat(tui-go): interactive clarification question view

Render stage clarification questions as an AskUserQuestion-style form:
header chip, prompt, selectable option chips, and a free-text custom slot.
Arrow/hjkl nav, space to select, e for custom, enter to submit. Submit
guards on all-answered and sends ClarificationResponse; the parked stage
re-runs with the answers in context.

apps/tui-go/internal/app/view.go

@@ -55,6 +55,9 @@ func (m Model) View() string {
 		m.renderFooter(),
 	)
 
+	if m.displayState() == StateClarification {
+		return m.center(m.clarificationModal())
+	}
 	if m.overlay != OverlayNone {
 		return m.renderOverlay(base)
 	}
@@ -218,6 +221,9 @@ func (m Model) renderFooter() string {
 	case m.displayState() == StateApproval:
 		// Approval actions live in the band itself; the footer offers navigation only.
 		hints = []string{hint("l", "back"), hint("e", "events"), hint("q", "quit")}
+	case m.displayState() == StateClarification:
+		// The question form owns its keys; the footer mirrors the essentials.
+		hints = []string{hint("←→", "option"), hint("↑↓", "question"), hint("spc", "select"), hint("enter", "submit"), hint("esc", "later")}
 	case m.displayState() == StateIdle:
 		if nrw {
 			hints = []string{hint("i", "name"), hint("/", "filter"), hint("w", "wf"), hint("p", "cmds"), hint("q", "quit")}