[Kernel/Quant] Remove AQLM

[mgoin]

We loved AQLM, but it did not see much usage so I think we should remove to reduce complexity.

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[gemini-code-assist]

Code Review

This pull request removes all code related to AQLM quantization. The changes are mostly deletions of files and code blocks, and they seem consistent and correct in achieving the goal of removing AQLM support. However, I found one change in tests/models/quantization/test_gguf.py that seems unrelated to AQLM removal, where some tests are being disabled. This might be an accidental commit and should be reviewed.

[yewentao256]

LGTM, thanks for the work!

[yewentao256]

Please also deal with the DCO issue