docs(reasoning content): 📝 deepseek-r1 parser support qwq

[xihuai18]

Motivation

Modifications

Test QwQ and add docs.

Checklist

• Format your code according to the Code Formatting with Pre-Commit.
• Add unit tests as outlined in the Running Unit Tests.
• Update documentation / docstrings / example tutorials as needed, according to Writing Documentation.
• Provide throughput / latency benchmark results and accuracy evaluation results as needed, according to Benchmark and Profiling and Accuracy Results.
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[zhaochenyang20]

@xihuai18 Great. Will merge this.