[sglang] fix: Fix qwen2vl weight keys issue

[hebiao064]

What does this PR do?

Reapply #1880

A earlier PR: #2365 accidentally removed the weight key conversion:

Why it wasn't caught by CI?

Because all CI are based on transformers 4.51, while the issue only happens for transformer 4.52

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[gemini-code-assist]

Code Review

This pull request correctly re-introduces a call to convert_weight_keys to fix a weight key issue with qwen2vl models, which was accidentally removed in a previous change. The reordering of operations in the wake_up method also appears logical.

However, my review identified a potential critical issue in the convert_weight_keys function itself. It lacks protection against key collisions during the conversion process, which could lead to silent loss of model weights and result in a partially loaded, incorrect model. I've added a comment highlighting this risk at the point of use.

To prevent similar regressions in the future, I also recommend updating the CI pipeline to include tests with more recent versions of the transformers library, as noted in the PR description.

[hebiao064]

@chenhaiq would you please take a look, thanks!