Add server-side ELO ratings

scripts/ui/dashboard.gd

@@ -5,7 +5,7 @@ const Style := preload("res://scripts/ui/ui_style.gd")
 var main: Control
 var status_label: Label
 var daily_label: Label
-var xp_label: Label
+var elo_label: Label
 var streak_label: Label
 var bank_label: Label
 var error_label: Label
@@ -17,6 +17,8 @@ func _ready() -> void:
 	add_theme_constant_override("separation", 18)
 	if not QuestionBankService.questions_changed.is_connected(_refresh):
 		QuestionBankService.questions_changed.connect(_refresh)
+	if not QuestionBankService.ratings_changed.is_connected(_refresh):
+		QuestionBankService.ratings_changed.connect(_refresh)
 	if not ProfileService.profile_changed.is_connected(_refresh):
 		ProfileService.profile_changed.connect(_refresh)
 
@@ -36,7 +38,7 @@ func _ready() -> void:
 	add_child(summary)
 
 	daily_label = _add_metric(summary, "Today")
-	xp_label = _add_metric(summary, "Daily XP")
+	elo_label = _add_metric(summary, "ELO")
 	streak_label = _add_metric(summary, "Streak")
 	bank_label = _add_metric(summary, "Question Bank")
 
@@ -115,7 +117,10 @@ func _refresh() -> void:
 	if progress > 100:
 		progress = 100
 	daily_label.text = "Today\n%d/%d questions\n%d%% complete" % [answered, goal, progress]
-	xp_label.text = "Daily XP\n%d XP earned" % int(profile.get("daily_xp_earned", 0))
+	elo_label.text = "ELO\n%d overall\n%d rated" % [
+		QuestionBankService.overall_elo,
+		QuestionBankService.rated_question_count
+	]
 	streak_label.text = "Streak\n%d current\n%d best" % [
 		int(profile.get("current_streak", 0)),
 		int(profile.get("best_streak", 0))