[Feature]: Add cost mapping for Deepseek V4 Flash and Pro

[hxt365]

Check for existing issues

• I have searched the existing issues and checked that my issue is not a duplicate.

The Feature

Deepseek has recently released deepseek-v4-flash and deepseek-v4-pro: https://api-docs.deepseek.com/quick_start/pricing
Please add the cost mapping for the models

Motivation, pitch

Deepseek models are powerful and cheap, hence very popular

What part of LiteLLM is this about?

SDK (litellm Python package)

LiteLLM is hiring a founding backend engineer, are you interested in joining us and shipping to all our users?

No

Twitter / LinkedIn details

No response