Add Code World Model (CWM) (#41199)
* [wip][cwm] Code World Model stubs and setup in HF Transformers
* [wip] Get other things working
* [wip] Working
* Tokenizer pad
* fix: cwm window attn
* temp remove test
* temp remove test
* Fixes
* Temporarily add auto config remapping option until VLLM 0.11 is out
* Fix model type and add layer validation
* Lint, remove CwmForSequenceClassification
* Lint, tests
* Remove CwmForSequenceClassification
* Lint
* Remove intermediary layer expors/doc errorss, fix tests
* Lint
* run python utils/sort_auto_mappings.py --check_only
* Remove Cwm processor mapping, get check_repo passing
* Remove CwmTextConfig from test
* Add docstring for CwmConfig
* remove global_window and window_pattern params from config
* Fix docstrings
* Revert change to auto docstring util
* lint
* Fixes minus test improvements
* Alter tests to simply check logits
* lint
* Have slow tests use repo, make CwmPretrainedModel passthrough
* Remove decoder layer implementation, use Llama3Decoder + CwmAttetion
* Use linear w/o bias for CwmAttention, add token-level integration test
* Don't ignore config attention bias
* Remove attention bias parameter entirely from config
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Co-authored-by: galco <galco@meta.com>
