Add a setting to turn off follow-up questions

The optional "FOLLOW-UP QUESTIONS" reinforcement section shown during
answer review is now gated behind a Settings toggle (on by default),
persisted locally the same way as dark mode and interface sounds.

scripts/ui/question_player.gd

@@ -1811,6 +1811,9 @@ func _render_review_followups() -> void:
 	if review_followups_content == null:
 		return
 	_clear_container_children(review_followups_content)
+	if not BlockSessionService.show_review_followups:
+		review_followups_section.visible = false
+		return
 	var question := BlockSessionService.get_current_question()
 	var authored: Array = question.get("review_followups", [])
 	if review_followup_states.size() != authored.size():

scripts/ui/settings_screen.gd

@@ -9,6 +9,7 @@ const CORE_BLOCK_SIZE_STEP := 5
 var main: Control
 var theme_toggle: CheckButton
 var sound_toggle: CheckButton
+var followups_toggle: CheckButton
 var question_scale_value_label: Label
 var ccs_scale_value_label: Label
 var core_block_size_value_label: Label
@@ -59,6 +60,13 @@ func _ready() -> void:
 	sound_toggle.toggled.connect(UISoundService.set_sounds_enabled)
 	content.add_child(sound_toggle)
 
+	followups_toggle = CheckButton.new()
+	followups_toggle.text = "Follow-up questions"
+	followups_toggle.tooltip_text = "Optional reinforcement questions shown after you answer"
+	followups_toggle.custom_minimum_size = Vector2(0, 52)
+	followups_toggle.toggled.connect(BlockSessionService.set_show_review_followups)
+	content.add_child(followups_toggle)
+
 	content.add_child(_build_text_scale_row("Question bank text size", "question"))
 	content.add_child(_build_text_scale_row("CCS case text size", "ccs"))
 	content.add_child(_build_core_block_size_row())
@@ -93,6 +101,7 @@ func _ready() -> void:
 func on_show(_payload: Variant = null) -> void:
 	theme_toggle.set_pressed_no_signal(UIThemeService.is_dark_mode())
 	sound_toggle.set_pressed_no_signal(UISoundService.are_sounds_enabled())
+	followups_toggle.set_pressed_no_signal(BlockSessionService.show_review_followups)
 	_refresh_text_scale_labels()