WebGPU: Fix highlight layer in fast snapshot rendering mode (#16523)

See
https://forum.babylonjs.com/t/highlight-breaks-when-using-webgpu-with-snapshot-rendering/58023

Author: Popov72

packages/dev/core/src/Materials/uniformBuffer.ts

@@ -1175,6 +1175,10 @@ export class UniformBuffer {
                 this._buffer = dataBuffer;
                 this._createBufferOnWrite = false;
                 this._currentEffect = undefined as any;
+                if (this._buffers[b][1]) {
+                    this._bufferData.set(this._buffers[b][1]!);
+                }
+                this._valueCache = {};
                 // The following line prevents the current buffer (_buffer / _bufferIndex) from being updated during subsequent calls to updateXXX() due to a call to _checkNewFrame()
                 // If we called setDataBuffer, it means that we want to update the buffer we just defined and not another one (_checkNewFrame() can modify the current buffer).
                 this._currentFrameId = this._engine.frameId;