Continuous batching refactor (#40426)
* Rework of the CB example
* Further rework of CB example
* Refactor PA cache, slice on tokens, add debug prints -- WIP
* Slice cache -- WIP
* Added a mechanism to check batched outputs in CB script
* Less logging, debug flag for slice, !better reset! -- WIP
* QOL and safety margins
* Refactor and style
* Better saving of cb example
* Fix
* Fixes and QOL
* Mor einformations about metrics
* Further logging
* Style
* Licenses
* Removed some comments
* Add a slice input flag
* Fix in example
* Added back some open-telemetry deps
* Removed some aux function
* Added FA2 option to example script
* Fixed math (all of it)
* Added a simple example
* Renamed core to classes
* Made allocation of attention mask optionnal
* Style
