deepseek-chat and deepseek-reasoner upgraded to DeepSeek-V3.2-Exp

Both deepseek-chat and deepseek-reasoner have been upgraded to DeepSeek-V3.2-Exp.

• deepseek-chat corresponds to DeepSeek-V3.2-Exp's non-thinking mode
• deepseek-reasoner corresponds to DeepSeek-V3.2-Exp's thinking mode

For more details, please refer to this documentation.