fix(recipe): change solar-open2 served-model-name to solar
The UpstageAI vLLM fork (v0.22.0-solar-open2) uses 'solar' as the
canonical model name in its tokenizer config. Using 'solar-open2-250b'
causes a mismatch between the served model name and the tokenizer's
expected name, leading to incorrect token decoding in some edge cases.
Changing to 'solar' aligns with the fork's internal naming.
