Is your feature request related to a problem? Please describe.
I have reviewed the configurations related to DeepSeek. The relevant descriptions in #312 are too outdated. For example, the deepseek-code model has been replaced by deepseek-reasone.

apis:
  # DeepSeek
  # https://api-docs.deepseek.com/zh-cn/
  deepseek:
    base-url: https://api.deepseek.com/
    api-key:
    api-key-env: DEEPSEEK_API_KEY
    models:
      deepseek-chat:
        aliases: ["chat"]
        max-input-chars: 384000
      deepseek-reasoner:
        aliases: ["r1"]
        max-input-chars: 384000

Describe the solution you'd like
Unfortunately, deepseek-reasoner does not comply with OpenAI's API specifications, only deepseek-chat does. Therefore, a completely new custom provider is needed to handle them separately. It must be integrated according to the description in the documentation.
deepseek docs API

Describe alternatives you've considered
At present, my only alternative is to use it through a browser.