[Bugfix] Fix ModernBert load & Enable sliding window attention for bidirectional attention.

[noooop]

Essential Elements of an Effective PR Description Checklist

• The purpose of the PR, such as "Fix some issue (link existing issues this PR will resolve)".
• The test plan, such as providing test command.
• The test results, such as pasting the results comparison before and after, or e2e results
• (Optional) The necessary documentation update, such as updating supported_models.md and examples for a new model.

Purpose

Fix #22620

Test Plan

pytest -s -vvv tests/models/language/pooling/test_gte.py::test_rerank_models_mteb

Test Result

pass

(Optional) Documentation Update

Known Issues

Does not support fp32

NotImplementedError: FlexAttention does not support sliding window yet.

[gemini-code-assist]

Code Review

This pull request provides a set of crucial bug fixes for the ModernBert model implementation, ensuring its correct loading and functionality within vLLM. The changes address several key areas: a data type mismatch in the pooling layer's head, incorrect weight loading paths, and an erroneous argument name in a forward pass, all of which are critical for the model's operation. The removal of SupportsV0Only is also a positive step towards broader compatibility. Additionally, a new test file is introduced with well-designed tests for both classification and reranking models, validating the fixes and improving test coverage. The overall changes are excellent and significantly improve the reliability of ModernBert models.

[github-actions]

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[mergify]

This pull request has merge conflicts that must be resolved before it can be
merged. Please rebase the PR, @noooop.

https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/working-with-forks/syncing-a-fork

[maxdebayser]

I've pushed the sliding attn changes directly on your PR, I hope that's OK.

[noooop]

I've pushed the sliding attn changes directly on your PR, I hope that's OK.

The local test runs successfully on my machine.

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Looking forward to future cooperation!

[DarkLight1337]

Thanks, let's see if the tests pass