fix(ep): include CPU in vendor compatibility

[Zhipeng Wang (timenick)]

Summary

• include CPU manufacturer and name in vendor detection for EPs that support CPU devices
• scope build and session compatibility checks to the concrete target device, preventing CPU vendors from authorizing unrelated GPU or NPU selections
• cache CPU, GPU, and NPU detection independently and preserve strict hardware-detection failures
• add regression coverage for Intel CPU + NVIDIA GPU hosts, accelerator-only EP isolation, custom catalogs, and downstream selection

Design

EP-wide inventory checks aggregate only the device classes declared in EP_SUPPORTED_DEVICES. Device-selection paths pass their concrete device class, so OpenVINO is compatible through an Intel CPU without being treated as compatible for a non-Intel GPU or NPU.

Closes #1274