feat(client): 完成40250客户端核心功能1:1对齐与桥梁高度采样修复

- 桥梁与静态物体高度采样修复：
  - 严格对齐 40250 CMapOutdoor::GetHeight 与 CAttributeInstance::GetHeight
  - 解析 .mdatr 中的 AttributeHeight 网格，使用 is_in_triangle_2d 准确计算桥面多边形平面方程
  - sample_height 查询邻近区块并返回 fMAX(fObjectHeight, fTerrainHeight)，彻底解决走上桥面穿透掉入水底/河床的问题
  - 新增 test_bridge_height_parity.gd 自动化对拍测试
- 40250 怪物击杀经验动效：
  - 1:1 实现 FLY_EXP(0) / FLY_HP / FLY_SP 粒子轨迹与爆炸吸附
- 40250 客户端全系统功能对齐（Batches 1-31）：
  - 包含公会、交易、骑乘、变身、钓鱼、采矿、商城、信件、结婚、地牢等 134 套对拍系统与自动化回归测试
- 文档沉淀：
  - 新增 docs/CLIENT-PARITY-AUDIT-AND-FIX-GUIDE.md 客户端对拍缺陷发现与修复工程指南

project/horse_system.gd

@@ -0,0 +1,138 @@
+# horse_system.gd —— 40250 战马与骑乘系统 1:1 规则引擎
+# 严格对照：
+#   metin2/src/server/game/src/cmd_general.cpp:45-100 (do_user_horse_ride / back / feed)
+#   metin2/src/server/game/src/cmd_general.cpp:2426-2465 (do_ride)
+#   root/game.py:344, 461-490 (Ctrl+G, Ctrl+H, Ctrl+B, Ctrl+F)
+#   ClientVS22/UserInterface/InstanceBase.cpp (IsMountingHorse, 5.0m attack range)
+extends RefCounted
+
+const ITEM_HORSE_PICTURE := 50051   # 初级马画 (Lv 1 - 10)
+const ITEM_HORSE_MEDAL := 50052     # 战斗马牌 (Lv 11 - 20)
+const ITEM_HORSE_MILITARY := 50053  # 军马牌 (Lv 21 - 30)
+
+const ITEM_FOOD_HAY := 50057        # 干草
+const ITEM_FOOD_CARROT := 50054     # 胡萝卜
+const ITEM_FOOD_GINSENG := 50058    # 人参
+
+const HORSE_TIER_NONE := 0
+const HORSE_TIER_BEGINNER := 1      # 普通马
+const HORSE_TIER_COMBAT := 2        # 战斗马（可马上砍怪）
+const HORSE_TIER_MILITARY := 3      # 军马（可使用马术技能）
+
+# 召唤消耗 SP
+const SUMMON_SP_COST := {
+	HORSE_TIER_BEGINNER: 100,
+	HORSE_TIER_COMBAT: 200,
+	HORSE_TIER_MILITARY: 300,
+}
+
+# 基础召唤成功率
+const BASE_SUMMON_CHANCE := {
+	HORSE_TIER_BEGINNER: 10,
+	HORSE_TIER_COMBAT: 20,
+	HORSE_TIER_MILITARY: 30,
+}
+
+# 骑乘时战斗与拾取距离加成（从 300cm 扩至 500cm，1:1 ClientVS22）
+const WALKING_ATTACK_RANGE := 3.0
+const MOUNTED_ATTACK_RANGE := 5.0
+
+# 判定马牌对应的级别与需求
+static func get_horse_tier_from_item(vnum: int) -> int:
+	match vnum:
+		ITEM_HORSE_PICTURE: return HORSE_TIER_BEGINNER
+		ITEM_HORSE_MEDAL: return HORSE_TIER_COMBAT
+		ITEM_HORSE_MILITARY: return HORSE_TIER_MILITARY
+		_: return HORSE_TIER_NONE
+
+# 所需饲料
+static func get_required_food(tier: int) -> int:
+	match tier:
+		HORSE_TIER_BEGINNER: return ITEM_FOOD_HAY
+		HORSE_TIER_COMBAT: return ITEM_FOOD_CARROT
+		HORSE_TIER_MILITARY: return ITEM_FOOD_GINSENG
+		_: return 0
+
+# 召唤几率计算（1:1 char_horse.cpp: HorseSummon）
+# chance = base_chance + horse_summon_skill_level * 10, max 100
+static func calculate_summon_chance(tier: int, summon_skill_level: int) -> int:
+	var base: int = BASE_SUMMON_CHANCE.get(tier, 10)
+	return mini(100, base + summon_skill_level * 10)
+
+# 执行召唤判定
+static func try_summon_horse(
+	tier: int,
+	current_sp: int,
+	summon_skill_level: int,
+	roll_val := -1
+) -> Dictionary:
+	var sp_cost: int = SUMMON_SP_COST.get(tier, 100)
+	if current_sp < sp_cost:
+		return {"success": false, "err": "insufficient_sp", "sp_cost": sp_cost}
+
+	var chance := calculate_summon_chance(tier, summon_skill_level)
+	var dice := roll_val if roll_val > 0 else (randi() % 100 + 1)
+	var success := (dice <= chance)
+
+	return {
+		"success": success,
+		"sp_cost": sp_cost,
+		"tier": tier,
+		"err": "" if success else "summon_failed",
+	}
+
+# 执行 /user_horse_ride (Ctrl+H) 状态机 (cmd_general.cpp:45)
+static func handle_user_horse_ride(
+	is_riding: bool,
+	is_horse_summoned: bool,
+	is_other_mount: bool,
+	is_dead_or_stun: bool
+) -> Dictionary:
+	if is_dead_or_stun:
+		return {"action": "none", "err": "dead_or_stun"}
+
+	if not is_riding:
+		if is_other_mount:
+			return {"action": "none", "err": "already_mounting_other", "msg": "已经在使用其他坐骑。"}
+		if not is_horse_summoned:
+			return {"action": "none", "err": "horse_not_summoned", "msg": "请先召唤马匹。"}
+		return {"action": "start_riding", "err": "", "is_riding": true}
+	else:
+		return {"action": "stop_riding", "err": "", "is_riding": false}
+
+# 执行 /user_horse_back (Ctrl+B) 状态机 (cmd_general.cpp:75)
+static func handle_user_horse_back(
+	is_riding: bool,
+	is_horse_summoned: bool
+) -> Dictionary:
+	if is_riding:
+		return {"action": "none", "err": "must_dismount_first", "msg": "请先下马。"}
+	if not is_horse_summoned:
+		return {"action": "none", "err": "horse_not_summoned", "msg": "请先召唤马匹。"}
+	return {"action": "unsummon", "err": "", "is_horse_summoned": false, "msg": "已送回马匹。"}
+
+# 执行 /ride (Ctrl+G) 状态机 (cmd_general.cpp:2426)
+static func handle_ride(
+	is_riding: bool,
+	is_horse_summoned: bool,
+	has_ride_item: bool
+) -> Dictionary:
+	if is_riding:
+		return {"action": "stop_riding", "err": "", "is_riding": false}
+	if is_horse_summoned:
+		return {"action": "start_riding", "err": "", "is_riding": true}
+	if has_ride_item:
+		return {"action": "mount_item", "err": "", "is_riding": true}
+	return {"action": "none", "err": "cannot_ride", "msg": "没有可骑乘的马匹或坐骑。"}
+
+# 喂食逻辑 (Ctrl+F)
+static func handle_user_horse_feed(
+	tier: int,
+	food_item_vnum: int
+) -> Dictionary:
+	var req_food := get_required_food(tier)
+	if req_food == 0:
+		return {"success": false, "msg": "当前没有出战马匹。"}
+	if food_item_vnum != req_food:
+		return {"success": false, "msg": "这种食物不适合当前马匹。"}
+	return {"success": true, "consumed_vnum": req_food, "msg": "战马饱餐了一顿，恢复了活力！"}