feat(ui): add commentary helpers and constants

src/ui/scenes/training_room.gd

@@ -1,6 +1,10 @@
 extends Control
 
 const CARD_NODE_SCENE := preload("res://src/ui/components/card_node.tscn")
+const FLIGHT_DURATION := 0.30
+const COMMENTARY_FADE_IN := 0.20
+const COMMENTARY_HOLD := 0.60
+const COMMENTARY_FADE_OUT := 0.30
 
 var controller: TrainingController
 var table_cards: Array[CardNode] = []
@@ -12,6 +16,8 @@ var table_cards: Array[CardNode] = []
 @onready var status_label: Label = $StatusLabel
 @onready var guide_label: Label = $GuideLabel
 @onready var table_label: Label = $TableLabel
+@onready var commentary_label: Label = $CommentaryLabel
+@onready var table_card_root: Control = $TableCardRoot
 
 func _ready() -> void:
 	if play_button:
@@ -124,6 +130,24 @@ func _clear_table_cards() -> void:
 		cn.queue_free()
 	table_cards.clear()
 
+func _show_commentary(player_idx: int, play: HandEvaluator.EvaluatedPlay) -> void:
+	if not commentary_label:
+		return
+	var pname := controller.game_state.player_names[player_idx]
+	var type_name := _get_type_name(play.type)
+	commentary_label.text = "%s 出了 %s（%d张，主阶=%d）" \
+		% [pname, type_name, play.cards.size(), play.primary_rank]
+	commentary_label.modulate.a = 0.0
+	var t := create_tween()
+	t.tween_property(commentary_label, "modulate:a", 1.0, COMMENTARY_FADE_IN)
+
+
+func _find_hand_node(card: Card) -> CardNode:
+	for cn in hand_area.card_nodes:
+		if cn.card_data != null and cn.card_data.card_id == card.card_id:
+			return cn
+	return null
+
 func _get_error_message(error_code: int) -> String:
 	match error_code:
 		1: return "无效的牌型组合"