Restore cuda graphs to continuous batching (#41421)
* Type hints and small fixes
* Remove unusued params
* Made slice inputs the default
* ruffed
* Updated some var name and moved index slicing
* Logging arg in example
* Added some padding debug var and reformat out cg
* First working CG, fixe size
* Working flexible CG
* CG are compatible with all implementations
* Fixed CG API
* Update example
* Documentation
* Fix padding tokens in FA
* Review compliance
* Better doc around weird bug
* Style
* Fix for sliding with CG
