feat(UI): 添加游戏开始界面和难度选择功能

实现游戏开始界面，包含难度选择滑块和开始按钮
修改游戏规则初始难度为10并调整掉落物品数量计算
添加游戏开始条件检查，确保运行时间超过3秒且没有敌人时显示制作饲料界面

scripts/Contents/Panels/Starter.gd

@@ -0,0 +1,16 @@
+@tool
+extends FullscreenPanelBase
+
+@onready var diffEdit: HSlider = $"%diffEdit"
+@onready var startBtn: Button = $"%startBtn"
+@onready var levelShow: Label = $"%levelShow"
+
+func _ready():
+	startBtn.pressed.connect(
+		func():
+			Wave.next()
+			UIState.closeCurrentPanel()
+	)
+func _physics_process(_delta):
+	levelShow.text = "%s/10" % diffEdit.value
+	GameRule.difficulty = diffEdit.value

scripts/Statemachine/EntityBase.gd

@@ -255,7 +255,7 @@ func tryDie(by: BulletBase):
 		var item = drops[drop]
 		var count = ceil(randf_range(dropCounts[drop].x, dropCounts[drop].y))
 		for i in range(count):
-			ItemDropped.generate(item, randi_range(0, int(sqrt(count))), position + MathTool.randv2_range(GameRule.itemDroppedSpawnOffset))
+			ItemDropped.generate(item, randi_range(1, int(sqrt(count) + GameRule.difficulty)), position + MathTool.randv2_range(GameRule.itemDroppedSpawnOffset))
 	if MathTool.rate(
 		GameRule.appleDropRate +
 		by.launcher.fields.get(FieldStore.Entity.DROP_APPLE_RATE) +
@@ -268,10 +268,11 @@ func tryDie(by: BulletBase):
 		fields[FieldStore.Entity.MAX_HEALTH] * randf_range(1 - GameRule.beachballOffset, 1 + GameRule.beachballOffset),
 		position + MathTool.randv2_range(GameRule.itemDroppedSpawnOffset)
 	)
+	if isPlayer():
+		if UIState.player == self:
+			UIState.setPanel("GameOver", [displayName, by.launcher.displayName])
 	EffectController.create(preload("res://components/Effects/DeadBlood.tscn"), texture.global_position).shot()
 	await die()
-	if isPlayer() and UIState.player == self:
-		UIState.setPanel("GameOver", [displayName, by.launcher.displayName])
 func tryHeal(count: float):
 	if inventory[ItemStore.ItemType.APPLE] > 0 and health < fields.get(FieldStore.Entity.MAX_HEALTH):
 		inventory[ItemStore.ItemType.APPLE] -= 1

scripts/Statemachine/UIState.gd

@@ -19,6 +19,7 @@ func _ready():
 	energyPercent = $"%percent"
 	itemCollect = $"%itemCollect"
 	skillIconContainer = $"%skillContainer"
+	setPanel("Starter")
 func _process(_delta):
 	bossbar.visible = !!bossbar.entity
 func _physics_process(_delta):

scripts/Tools/GameRule.gd

@@ -1,7 +1,7 @@
 class_name GameRule
 
 static var deadReasons: Array = JsonTool.parseJson("res://resources/constants/deadReasons.json")
-static var difficulty: float = 1 # 难度倍数，可以写小数
+static var difficulty: float = 10 # 难度倍数，可以写小数
 static var allowFriendlyFire: bool = false # 是否允许友军伤害
 static var bulletSpeedMultiplier: float = 1 # 子弹速度倍率
 static var damageOffset: float = MathTool.percent(20) # 伤害随机浮动比例

scripts/Tools/WorldManager.gd

@@ -8,10 +8,9 @@ static var runningTime: int = 0
 func _ready():
 	tree = get_tree()
 	rootNode = self
-	print(GameRule.deadReasons)
 func _physics_process(delta):
 	runningTime += delta * 1000
-	if EntityBase.mobCount() == 0:
+	if EntityBase.mobCount() == 0 and runningTime > 3000:
 		UIState.setPanel("MakeFeed")
 
 static func getTime():