Add Olmo3 model (#40778)
* transformers add-new-model-like for Olmo3
* Implement modular Olmo3
* Update Olmo3 tests
* Copy Olmo2 weight converter to Olmo3
* Implement Olmo3 weight converter
* Fix code quality errors
* Remove unused import
* Address rope-related PR comments
* Update Olmo3 model doc with minimal details
* Fix Olmo3 rope test failure
* Fix 7B integration test
