Migrate test_utils, test_schema_check for xpu and add checkpoint.py f…

[shangerxin]

Description

Fixes #114850, we will port test utils and schema check to Intel GPU
We could enable Intel GPU with following methods and try the best to keep the original code styles:

Changes

1. Get device type with from accelerator and get_devtype helper method
2. Replace the requires cuda statement to device_type.
3. Add HAS_XPU and HAS GPU check to replace some of the HAS_XPU etc.

[Copilot]

Pull Request Overview

This PR migrates test utilities and schema checking functionality to support Intel XPU (GPU) devices by porting existing CUDA-specific test files. The migration follows a pattern of making device-agnostic changes while preserving original code structure.

• Creates device-agnostic test infrastructure for Intel XPU support
• Introduces a checkpoint utility module for XPU test environments
• Enables device type detection using accelerator helpers instead of hardcoded CUDA references

Reviewed Changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated 9 comments.

File	Description
test/xpu/test_utils.py	Migrates utility tests from CUDA to device-agnostic approach using HAS_GPU and device_type variables
test/xpu/test_schema_check.py	Ports schema validation tests to XPU with device type instantiation for cpu/cuda/xpu
test/xpu/checkpoint.py	Adds comprehensive checkpoint functionality supporting XPU device detection and state management

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