Initial spec and L0 implementation (#19018)

This patch introduces new SYCL and UR extensions for exporting memory.

 - SYCL: `sycl_ext_oneapi_memory_export`
 - UR: `EXP-MEMORY-EXPORT`

The exported memory handles can be imported by external APIs and
operated on without the need to perform costly copy operations.

Three new SYCL APIs are added by this extension:

 - `alloc_exportable_device_mem`
 - `export_device_mem_handle`
 - `free_exportable_mem`

Currently we can only export "linear" memory layouts. Exporting other
memory layouts, such as "optimal" (Vulkan equivalent
`VK_IMAGE_TILING_OPTIMAL`) is not currently supported by any UR adapter
APIs.

Author: przemektmalon