Fix/siglip2 pooling comment
Author: sameerajashyam
Pull request: yes

# What does this PR do?
This PR updates the Siglip2TextModel to simplify and clarify the logic for generating the pooled output. Specifically, it removes the ambiguous conditional logic and comment regarding the use of eos_token_id or padding tokens, and instead uses the last token's hidden state as the pooled representation

Additional Changes:
Adds a dedicated unit test in test_text_model.py to validate the forward pass behavior.
Cleans up minor formatting issues in the test file (ruff compliant).

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Fixes # (issue)


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Comments:
cc @qubvel 

@sameerajashyam PR just need to update the comment, if you are using AI to open a PR please make sure changes are relevant 🤗 

Hi @qubvel 
i am bit confused . in starting i done changes in modeling_siglip2.py file and updated comment 
and submitted and later i found the modeling_siglip2.py file is auto generated from 
modular_siglip2.py file so i thought it was wrong to edit in modelling_siglip2.py file so i had removed my changes . i want to know from which file it is generated .Because i had    deleted the comment and run the file after i can see the same comment again in modeling_siglip2.py. when i run this command in git i saw the line is present  in  only modelling_siglip2.py file .
$ grep -Rn "EOS tokenization"
src/transformers/models/siglip/modeling_siglip.py:667:        # Assuming "sticky" EOS tokenization, last token is always EOS.
src/transformers/models/siglip2/modeling_siglip2.py:691:        # Assuming "sticky" EOS tokenization, last token is always EOS.
i am bit confused ?



You just need to modify `src/transformers/models/siglip/modeling_siglip.py`, then run `make fix-copies` and commit the changes (changes will be automatically propagated to siglip2 as well)

**[For maintainers]** Suggested jobs to run (before merge)

run-slow: siglip, siglip2

Thanks for your support and guidance @zucchini-nlp @qubvel 

The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_39378). All of your documentation changes will be reflected on that endpoint. The docs are available until 30 days after the last update.