Qwen: [Docs] Add Developer Guide: How to Hack Any Transformers Model (#33979)

* docs: add example for separating q, k, v projections in SAM

* docs: How to Hack Any Transformers Model

* docs: remove changes from sam model docs

* Apply suggestions from code review

Co-authored-by: Arthur <48595927+ArthurZucker@users.noreply.github.com>

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Co-authored-by: Arthur <48595927+ArthurZucker@users.noreply.github.com>