chore: remove stale alias pointing to deepseek-flash

[wu21-web]

Description

There is a stale pointer named deepseek-v4-flash pointing to the new deepseek-flash.
Per the docs:

Therefore the deepseek-v4-flash should be removed, because it will always points towards to the new model.
The last PR updating the models list is incomplete.

deepseek-v4-pro is not effected because per the docs deepseek said it still supports v4 pro model

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• Refactoring (no functional changes)
• Documentation update
• CI / Build / Tooling

How Has This Been Tested?

• make test passes locally
• Manual testing (describe below)

Checklist

• My code follows the project's coding style (go fmt, go vet)
• I have performed a self-review of my code
• I have added tests that prove my fix is effective or my feature works
• New and existing unit tests pass locally with my changes
• I have updated the documentation accordingly (if applicable)
• I have signed the CLA
• I did not use AI/LLM to create this PR, or I disclosed the tool/model below and reviewed its output; I did not attribute commits to AI and will answer maintainer questions and review comments myself without AI/LLM.
  No AI used in any way

Related Issues

N/A

[github-actions]

✅ OpenCodeReview: Review complete: 0 finding(s) across 2 selected item(s).

[wu21-web]

@Qiyuanqiii I have considered all of the points you made upon creation, but I still created this. But we will see and get this reopened when that route is removed.

I created this despite knowing the compatibility route. And I belief DeepSeek will not serve deepseek-v4-flash model again.

LLM goes forwards, not backwards. This is a part of the OCR concept.

The timeout is 15 days.

[wu21-web]

@Qiyuanqiii I think you have a misunderstanding of the compatibility route. Or is it me?
We have 2 understandings here maybe:

1. The route is for programs that are still using the old model name so they won't fail.
2. The route is a substitute for the new model and will be removed later.

Which one is yours?

[wu21-web]

What models list? I had problem understanding.

[wu21-web]

@Qiyuanqiii Please 👍 if you don't have any doubts or questions. Let me know, thanks.