fix(tui): surface late clarifications and stop bg bleed on input + action rows

- clarDismissed was model-global but only reset when the clarification's
  session was selected on arrival, so a clarification for an unselected
  session stayed silently hidden. Reset on every arrival.
- input bar (in-session + launcher) only truncated lines, never padded to
  width, so the terminal backdrop bled through the right. Pad with padTo.
- action/narration/user rows prefixed plain (unstyled) spacers around their
  icons, leaving transparent gaps near the symbols. Use bg-styled spacers.

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

@@ -564,7 +564,7 @@ func (m Model) launcherInput(w int) string {
 	rule := lipgloss.NewStyle().Foreground(ruleColor).Background(t.P.Bg).Render(strings.Repeat("─", w))
 	boxLines := append([]string{rule}, content...)
 	for i, ln := range boxLines {
-		boxLines[i] = ansi.Truncate(ln, w, "")
+		boxLines[i] = padTo(ln, w, t.P.Bg)
 	}
 	box := strings.Join(boxLines, "\n")
 
@@ -713,8 +713,10 @@ func (m Model) renderInput() string {
 	rule := lipgloss.NewStyle().Foreground(ruleColor).Background(t.P.Bg).Render(strings.Repeat("─", m.width))
 	lines := append([]string{rule}, content...)
 	lines = append(lines, sub)
+	// Pad (not just truncate) every line to full width with the panel bg so the terminal backdrop
+	// can't bleed through the right of the placeholder / status sub-line (matches the frame fill).
 	for i, ln := range lines {
-		lines[i] = ansi.Truncate(ln, m.width, "")
+		lines[i] = padTo(ln, m.width, t.P.Bg)
 	}
 	return strings.Join(lines, "\n")
 }
@@ -797,7 +799,7 @@ func (m Model) buildTranscriptRows(w int) ([]string, []int) {
 				break
 			}
 			tag := lipgloss.NewStyle().Foreground(t.P.Accent).Background(t.P.Bg).Bold(true).Render("›")
-			rows = append(rows, tag+" "+t.span(e.Content, t.P.FgStrong))
+			rows = append(rows, tag+t.span(" ", t.P.Bg)+t.span(e.Content, t.P.FgStrong))
 		case "router":
 			// The router turn is model output: render it as markdown (bold,
 			// lists, headings, code) wrapped to the panel width. glamour applies
@@ -818,9 +820,9 @@ func (m Model) buildTranscriptRows(w int) ([]string, []int) {
 			lines := wrap(e.Content, w-2)
 			for i, ln := range lines {
 				if i == 0 {
-					rows = append(rows, diamond+" "+t.span(ln, t.P.FgStrong))
+					rows = append(rows, diamond+t.span(" ", t.P.Bg)+t.span(ln, t.P.FgStrong))
 				} else {
-					rows = append(rows, "  "+t.span(ln, t.P.FgStrong))
+					rows = append(rows, t.span("  ", t.P.Bg)+t.span(ln, t.P.FgStrong))
 				}
 			}
 			if s := metricsSuffix(e.Metrics); s != "" {
@@ -835,7 +837,7 @@ func (m Model) buildTranscriptRows(w int) ([]string, []int) {
 				break
 			}
 			icon := lipgloss.NewStyle().Foreground(t.P.Accent2).Background(t.P.Bg).Render(e.Icon)
-			rows = append(rows, "  "+icon+" "+t.span(e.Content, t.P.Dim))
+			rows = append(rows, t.span("  ", t.P.Bg)+icon+t.span(" ", t.P.Bg)+t.span(e.Content, t.P.Dim))
 		}
 	}
 	return rows, msgStart