fix: 修复 Unity 环境背景和字体问题

- 添加 Environment 对象和 EnvironmentManager 组件到场景
- 重新生成 SourceHanSansSC-Regular SDF 字体资产
- 添加 FixTMPFont 和 RegenerateChineseFont 编辑器工具

unity-client/Assets/main.unity

@@ -119,6 +119,73 @@ NavMeshSettings:
     debug:
       m_Flags: 0
   m_NavMeshData: {fileID: 0}
+--- !u!1 &318018866
+GameObject:
+  m_ObjectHideFlags: 0
+  m_CorrespondingSourceObject: {fileID: 0}
+  m_PrefabInstance: {fileID: 0}
+  m_PrefabAsset: {fileID: 0}
+  serializedVersion: 6
+  m_Component:
+  - component: {fileID: 318018868}
+  - component: {fileID: 318018867}
+  m_Layer: 0
+  m_Name: Environment
+  m_TagString: Untagged
+  m_Icon: {fileID: 0}
+  m_NavMeshLayer: 0
+  m_StaticEditorFlags: 0
+  m_IsActive: 1
+--- !u!114 &318018867
+MonoBehaviour:
+  m_ObjectHideFlags: 0
+  m_CorrespondingSourceObject: {fileID: 0}
+  m_PrefabInstance: {fileID: 0}
+  m_PrefabAsset: {fileID: 0}
+  m_GameObject: {fileID: 318018866}
+  m_Enabled: 1
+  m_EditorHideFlags: 0
+  m_Script: {fileID: 11500000, guid: 6aa9102a04d7544619ec0187e065eda9, type: 3}
+  m_Name: 
+  m_EditorClassIdentifier: Assembly-CSharp::TheIsland.Visual.EnvironmentManager
+  dawnSkyTop: {r: 0.98, g: 0.65, b: 0.45, a: 1}
+  dawnSkyBottom: {r: 1, g: 0.85, b: 0.6, a: 1}
+  dawnAmbient: {r: 1, g: 0.8, b: 0.6, a: 1}
+  daySkyTop: {r: 0.4, g: 0.7, b: 1, a: 1}
+  daySkyBottom: {r: 0.7, g: 0.9, b: 1, a: 1}
+  dayAmbient: {r: 1, g: 1, b: 0.95, a: 1}
+  duskSkyTop: {r: 0.3, g: 0.2, b: 0.5, a: 1}
+  duskSkyBottom: {r: 1, g: 0.5, b: 0.3, a: 1}
+  duskAmbient: {r: 1, g: 0.6, b: 0.4, a: 1}
+  nightSkyTop: {r: 0.05, g: 0.05, b: 0.15, a: 1}
+  nightSkyBottom: {r: 0.1, g: 0.15, b: 0.3, a: 1}
+  nightAmbient: {r: 0.3, g: 0.35, b: 0.5, a: 1}
+  cloudyTint: {r: 0.7, g: 0.7, b: 0.75, a: 1}
+  rainyTint: {r: 0.5, g: 0.55, b: 0.6, a: 1}
+  stormyTint: {r: 0.35, g: 0.35, b: 0.4, a: 1}
+  foggyTint: {r: 0.8, g: 0.8, b: 0.85, a: 1}
+  hotTint: {r: 1.1, g: 0.95, b: 0.85, a: 1}
+  sandColor: {r: 0.95, g: 0.87, b: 0.7, a: 1}
+  sandDarkColor: {r: 0.8, g: 0.7, b: 0.5, a: 1}
+  waterShallowColor: {r: 0.3, g: 0.8, b: 0.9, a: 0.8}
+  waterDeepColor: {r: 0.1, g: 0.4, b: 0.6, a: 0.9}
+  waveSpeed: 0.5
+  waveAmplitude: 0.1
+--- !u!4 &318018868
+Transform:
+  m_ObjectHideFlags: 0
+  m_CorrespondingSourceObject: {fileID: 0}
+  m_PrefabInstance: {fileID: 0}
+  m_PrefabAsset: {fileID: 0}
+  m_GameObject: {fileID: 318018866}
+  serializedVersion: 2
+  m_LocalRotation: {x: 0, y: 0, z: 0, w: 1}
+  m_LocalPosition: {x: 0, y: 0, z: 0}
+  m_LocalScale: {x: 1, y: 1, z: 1}
+  m_ConstrainProportionsScale: 0
+  m_Children: []
+  m_Father: {fileID: 0}
+  m_LocalEulerAnglesHint: {x: 0, y: 0, z: 0}
 --- !u!1 &851065943
 GameObject:
   m_ObjectHideFlags: 0
@@ -429,3 +496,4 @@ SceneRoots:
   - {fileID: 1918023635}
   - {fileID: 851065944}
   - {fileID: 1562380643}
+  - {fileID: 318018868}