Compress baked PNGs and tighten XPbr shadows with URP quality tweaks.

Add png_compress to the model pipeline and update TownSquare lighting plus MaleExplorer/plaza textures.

Co-authored-by: Cursor <cursoragent@cursor.com>

AIClient/Assets/Bundles/Shaders/XShader/XPbr_Base.hlsl

@@ -121,11 +121,10 @@ void InitializeInputData(Varyings input, half3 normalTS, out InputData inputData
     inputData.bakedGI = SAMPLE_GI(input.staticLightmapUV, input.vertexSH, inputData.normalWS);
 #else
     inputData.bakedGI = SampleSH(inputData.normalWS);
-#endif
-    // 仅在运行时全局环境光开启后才覆盖（Game.cs 设置）；否则保留场景自身 SH/光照贴图，
-    // 避免编辑器预览比 URP Lit 亮（旧写法无条件覆盖成硬编码的高强度三色环境光）
+    // 仅覆盖动态物体的探针环境光。光照贴图（含烘焙阴影/间接光）必须保留。
     if (_XRuntimeAmbientEnabled > 0.5h)
         inputData.bakedGI = SampleXRuntimeAmbient(inputData.normalWS);
+#endif
 
     inputData.normalizedScreenSpaceUV = GetNormalizedScreenSpaceUV(input.positionCS);
     inputData.shadowMask = SAMPLE_SHADOWMASK(input.staticLightmapUV);