Add FA2 and `sdpa` support for SigLIP (#31499)
* Rebase to main
* Fix attention implementation autoset for tex and vision configs
* Fixup
* Minor fixes
* Fix copies
* Fix attention_mask for FA2
* Add eqvivalence tests for siglip
* Remove right padding test
* Uncomment flaky
* Fix import
* Add to docs
* Fix test message
* Add sdpa
* Add sdpa equivalence test
* Add siglip sdpa to docs
* Fix typing for attention output
* Add sdpa tests
* Fix signature of FA2
* Autoset attn_implementation in config
* Rename bsz -> batch_size
* Move back autoset attn method
* Mark as flaky
* Correct attention mask padding
* [run-slow] siglip
* Add FA2 and sdpa docs
* Style fix
* Remove flaky for FA2 test
* Change attention implementation set
* Change attn_implementaiton propogation
* Fix typos
* Add modality to assert message
* Add more sdpa backends in test
* [run slow] siglip
* Add math sdpa backend for all options
* [run slow] siglip