fix(combat): 战斗逐项对齐 40250，修复移动 / 技能释放与武器挂点

- 连击类型由 combo_changed 驱动（SetComboSkillFlag，技能 122 等级）
- 命中判定改为 .msa 刀尖 Z 圆柱 vs .msm 防御球（hit_collision.gd 逐行移植）
- _register_hit 改为 map::insert 语义，修正命中上限
- 攻速同时缩放 GetAttackingElapsedTime 与攻击动作速率；按武器动作模式目录绑定攻击段
- 去掉本地连击超时，motion_bound 清命中表 / 连击段号
- __ProcessDataAttackSuccess：InsertDelay 硬直、physics_push.gd 击退 + GetBlendingPosition 同步、
  命中特效、__HitGood / __HitGreate / __HitStone 受击动作链与抖动（ui/hit_reaction.gd）
- ClassicSession::send_use_skill 不再夹带 CG_FLY_TARGETING
- mac 前进 / 后退方向与技能释放修复；武器按职业骨骼挂到手上
- 新增 hit_collision / physics_push / hit_view / net_world_push / weapon_attach 测试；
  gpu_pose_bounds / race_motion_assembly 适配 damage 随机变体
- 文档：CLIENT-GAP.md、CLIENT-GAP-FIX.md §3.5 / §3.7 与 C.5 增量 130

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Ft3kXpNdLbKEfg5uDLfqVF

extension/tests/net_classic_session_test.cpp

@@ -1185,6 +1185,16 @@ int main() {
 				out.back() == SEQUENCE_TABLE[seq], "guild invite answer wire");
 	}
 
+	// --- CG_USE_SKILL: PythonNetworkStreamPhaseGame.cpp SendUseSkillPacket sends
+	//     only the use-skill packet; fly-targeting is a separate caller decision ---
+	{
+		uint32_t seq = s.stream().sequence_index();
+		CHECK(s.send_use_skill(3, 8888), "use skill send");
+		auto out = drain(s);
+		CHECK(out.size() == sizeof(CGUseSkill) + 1 && out[0] == HDR_CG_USE_SKILL &&
+				out.back() == SEQUENCE_TABLE[seq], "use skill wire: no extra fly targeting");
+	}
+
 	// --- GC_CHAR_ADDITIONAL_INFO(136) with no matching pending GC_CHARACTER_ADD
 	//     is dropped and leaves the live entity untouched (§2.2) ---
 	{