Add character height scaler and assets

Add a new characterHeightScaler runtime component and characterHeightScalerEditor for Unity to auto-detect and apply a model scale to match the GKC standard height (capture/apply/reset, foot alignment, debug UI). Update DudeAvatar materials to assign main textures, clear legacy shader keywords and enable XR motion vectors. Modify launchObject material to use transparent surface settings, correct render queue/blend/ZWrite and disabled shadow/depth passes for proper particle rendering. Update ParticlesLight prefab to include UniversalAdditionalLightData and URP-related light fields (cookie size, shadow & rendering layers, etc.). Add new Flaco alien folder with prefabs/meshes and new house materials; remove some legacy alien FBX files. Also include Scene and ProjectSettings updates to accommodate the changes.

Assets/T-Pose.fbx.meta

@@ -3,7 +3,17 @@ guid: aa859a135ccab1c45943eab6c4434629
 ModelImporter:
   serializedVersion: 24200
   internalIDToNameTable: []
-  externalObjects: {}
+  externalObjects:
+  - first:
+      type: UnityEngine:Material
+      assembly: UnityEngine.CoreModule
+      name: Ch50_body
+    second: {fileID: -4565884009001823619, guid: 47dd5591ce018c74092f3b2fc673b384, type: 3}
+  - first:
+      type: UnityEngine:Material
+      assembly: UnityEngine.CoreModule
+      name: Ch50_body1
+    second: {fileID: -840037777384891287, guid: b339fb67cc9032e4888ef8f5f67a5ff2, type: 3}
   materials:
     materialImportMode: 1
     materialName: 0