Add qwen3 family

[tianyuan211]

What does this PR do?

Fixes # (issue)

Before submitting

• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
• Did you make sure to update the documentation with your changes?
• Did you write any new necessary tests?

[regisss]

On which version of Transformers is this PR based?

[tianyuan211]

On which version of Transformers is this PR based?

this is for Transformers 4.51, which includes the qwen3 model; I just add the qwen3 code part, not changing the other code which may influence the generation process.

[regisss]

@tianyuan211 Can you also add the following please?

• a text-generation test here: https://github.com/huggingface/optimum-habana/blob/main/tests/test_text_generation_example.py
• update this line in the README "Qwen2" --> "Qwen2 / Qwen3":

  optimum-habana/README.md

  Line 253 in 1734ad9

  | Qwen2 | <li>Single card</li> | <li>Single card</li> | <li>[language modeling](https://github.com/huggingface/optimum-habana/tree/main/examples/language-modeling)</li><li>[text generation](https://github.com/huggingface/optimum-habana/tree/main/examples/text-generation)</li> |

• same in the table of the doc:

  optimum-habana/docs/source/index.mdx

  Line 82 in 1734ad9

  | Qwen2 | <div style="text-align:left"><li>Single card</li></div> | <div style="text-align:left"><li>Single card</li></div> | <li>[language modeling](https://github.com/huggingface/optimum-habana/tree/main/examples/language-modeling)</li><li>[text generation](https://github.com/huggingface/optimum-habana/tree/main/examples/text-generation)</li> |