feat: support MiniMax-M2.7 Channel FP8 w8a8 on DCU.

[WenQ7]

Description

This PR adds MiniMax-M2 model registration, decoder/attention layers, tensor-parallel q/k RMSNorm, partial RoPE support, and DCU FP8 MoE execution with AITER kernels.

It enables MiniMax-M2.7-Channel-FP8-w8a8 to load and run on DCU with expert parallel MoE.

Related Issues

Change Type

• Bug fix
• New feature
• Performance improvement
• Refactor
• Documentation
• Test
• Build or CI

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