feat(tui): token metrics aggregation, plan overlay, tool reasoning, clar dismissal

#295 — include narration_llm tokens in changes-panel aggregate count
#296 — execution plan overlay (Ctrl+P in-session)
#298 — surface reasoning/CoT on tool-call turns in output view
#265 — dismiss clarification modal when answered externally (session.resumed)

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

@@ -141,6 +141,8 @@ func (m Model) renderOverlay(base string) string {
 		return m.center(m.grantsModal())
 	case OverlayGrantScope:
 		return m.center(m.grantScopeModal())
+	case OverlayPlan:
+		return m.center(m.planModal())
 	case OverlayHelp:
 		return m.center(m.helpModal())
 	}
@@ -926,6 +928,72 @@ func (m Model) toolPaletteModal() string {
 	return m.center(modal)
 }
 
+func (m Model) planModal() string {
+	t := m.theme
+	w := m.modalWidth()
+	s := m.session(m.selectedID)
+
+	var b strings.Builder
+	b.WriteString(m.titleLine("execution plan"))
+	if s != nil {
+		b.WriteString(mbg(t, "  —  "+s.WorkflowID, t.P.Dim))
+	}
+	b.WriteString("\n\n")
+
+	if s == nil || len(s.PlanStages) == 0 {
+		b.WriteString(mbg(t, "  no execution plan yet — stages appear once the plan is locked", t.P.Faint) + "\n")
+		if s != nil && s.CurrentStage != "" {
+			b.WriteString(mbg(t, "  current stage: "+s.CurrentStage, t.P.Accent2) + "\n")
+		}
+	} else {
+		goal := strings.TrimSpace(s.PlanGoal)
+		if goal != "" {
+			b.WriteString(mbg(t, "  goal", t.P.Faint) + "\n")
+			for _, ln := range wrap(goal, w-8) {
+				b.WriteString(mbg(t, "    "+ln, t.P.Fg) + "\n")
+			}
+			b.WriteString("\n")
+		}
+
+		b.WriteString(mbg(t, "  stages  ("+itoa(len(s.PlanStages))+" total)", t.P.Faint) + "\n")
+		idW := 0
+		for _, ps := range s.PlanStages {
+			if len(ps.ID) > idW {
+				idW = len(ps.ID)
+			}
+		}
+		for _, ps := range s.PlanStages {
+			var badge string
+			switch ps.Status {
+			case PlanPending:
+				badge = mbg(t, "  ○ pending", t.P.Faint)
+			case PlanRunning:
+				badge = lipgloss.NewStyle().Foreground(t.P.Accent).Background(t.P.BgPanel).Bold(true).Render("  ● running")
+			case PlanCompleted:
+				badge = lipgloss.NewStyle().Foreground(t.P.OK).Background(t.P.BgPanel).Render("  ✓ done")
+			case PlanFailed:
+				badge = lipgloss.NewStyle().Foreground(t.P.Bad).Background(t.P.BgPanel).Render("  ✗ failed")
+			}
+			stageLine := mbg(t, "  ", t.P.BgPanel) + badge + mbg(t, "  "+padRaw(ps.ID, idW), t.P.Fg)
+			if s.ToolsByStage != nil {
+				if tools, ok := s.ToolsByStage[ps.ID]; ok && len(tools) > 0 {
+					stageLine += mbg(t, "   ["+itoa(len(tools))+" tools]", t.P.Faint)
+				}
+			}
+			if budget, ok := s.TokenBudgetByStage[ps.ID]; ok && budget > 0 {
+				used := 0
+				if ps.ID == s.CurrentStage {
+					used = s.StageTokensUsed
+				}
+				stageLine += mbg(t, "  ("+itoa(used)+"/"+itoa(budget)+" tok)", t.P.Faint)
+			}
+			b.WriteString(stageLine + "\n")
+		}
+	}
+	b.WriteString("\n" + modalHints(t, [][2]string{{"esc", "close"}}))
+	return t.Overlay.Width(w).Render(b.String())
+}
+
 func (m Model) modelsModal() string {
 	t := m.theme
 	w := m.modalWidth()