add support for siliconflow (available for DeepSeek)

[wyycommu]

Issue

Hello, siliconflow provides an alternative to DeepSeek and I want to use it.
According to siliconflow's official documentation, I confirmed that it is compatible with OpenAI protocol and now it's available.

According to OpenAI compatible APIs I set the environment variables and confirmed that they are valid.

OPENAI_API_BASE=https://api.siliconflow.cn/v1
OPENAI_API_KEY=<my siliconflow key>

But when I run aider --model deepseek-ai/DeepSeek-V3, the result is as follows:

I have also tried using openai/xxx, but still failed to connect:

I feel quite confused about model_name. Please consider adding support for siliconflow . Thank you so much for developing this great project!

Version and model info

Aider v0.72.2
Model: deepseek-ai/DeepSeek-V3 with whole edit format

[gowinder]

Same request, need set alternative deepseek api base url

[wenwen12345]

Use openai/deepseek-ai/DeepSeek-V3 instead