Fixes huggingface/optimum-executorch#28.
The bundled `LlamaTokenizer` uses the standard Llama special tokens (`<s>`=1, `</s>`=2), but `config.json` and `generation_config.json` declared `bos_token_id=0, eos_token_id=1`. optimum-executorch exports `get_bos_id`/`get_eos_id` from the config, so the `.pte` carried 0/1 and `ExecuTorchModelForCausalLM.text_generation` correctly rejected the mismatch:
`ValueError: The tokenizer's bos_token_id=1 must be the same as the model's bos_token_id=0.`
This sets `bos_token_id=1, eos_token_id=2` in both files. No weights or tokenizer files changed. A companion PR updates the `executorch` revision (configs + regenerated `model.pte`).
