[Misc][LoRA] Add PEFTHelper for LoRA

[jeejeelee]

Motivation

This PR introduces a new PEFTHelper class to LoRA feature management , include:

• Built-in validation for unsupported feature (RSLoRA, DoRA and so on) , and enhances error handling by explicitly throwing exceptions for unsupported features.
• Make it easier to integrate future PEFT features
• consolidate long LoRA configuration

TODO

• Improve the logic
• Add unit test

[github-actions]

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[DarkLight1337]

Thanks for the refactor!