Update on "[ET-VK][11/n] copy_channel_offsets node"

1. Add a node `copy_channel_offsets` specifically for copying along the channel dimension, it needs extra attention at the boundaries due to channel packing.
1.1. `copy_channel_offsets` will be useful for `aten.cat` and `aten.split`.
2. Create `etvk.*` operators to facilitate testing. Add test case for both `copy_offset` and `copy_channel_offset`.

Differential Revision: [D56554426](https://our.internmc.facebook.com/intern/diff/D56554426/)

[ghstack-poisoned]

Author: yipjustin

backends/vulkan/runtime/graph/ops/impl/Copy.cpp

@@ -8,9 +8,6 @@
 
 #include <executorch/backends/vulkan/runtime/graph/ops/OperatorRegistry.h>
 
-#include <executorch/backends/vulkan/runtime/api/api.h>
-#include <executorch/backends/vulkan/runtime/graph/Logging.h>
-
 #include <executorch/backends/vulkan/runtime/graph/ops/impl/utils/DimUtils.h>
 #include <executorch/backends/vulkan/runtime/graph/ops/impl/utils/KernelUtils.h>
 #include <executorch/backends/vulkan/runtime/graph/ops/impl/utils/TensorUtils.h>