feat: add TokenMix as a model provider

[TokenMixAi]

Description

Adds TokenMix as a model provider. TokenMix is an OpenAI-compatible API gateway that exposes DeepSeek, Qwen, Kimi, GLM, MiniMax and other models through a single endpoint (https://api.tokenmix.ai/v1) and one API key, so it slots in as a standard OpenAI-compatible provider.

Usage:

models:
  - name: DeepSeek V4 Pro
    provider: tokenmix
    model: deepseek/deepseek-v4-pro
    apiKey: <YOUR_TOKENMIX_API_KEY>
    roles:
      - chat

Changes

• core/llm/llms/Tokenmix.ts — new provider class extending OpenAI (mirrors Tensorix/zAI)
• core/llm/llms/index.ts — register Tokenmix in LLMClasses
• packages/openai-adapters/src/types.ts — add tokenmix to the OpenAIConfigSchema provider union
• packages/openai-adapters/src/index.ts — route tokenmix through openAICompatible(...)
• gui/src/pages/AddNewModel/configs/providers.ts — Add-Model tile (models auto-detected via /v1/models)
• docs/customize/model-providers/more/tokenmix.mdx + docs/docs.json — docs page and nav entry

Checklist

• The relevant docs, if any, have been updated or created
• packages/openai-adapters typechecks clean (tsc --noEmit)
• Prettier formatting verified on all changed source/JSON files
• New provider follows the existing OpenAI-compatible provider pattern (Tensorix, zAI)

Tests

The provider is a thin OpenAI-compatible wrapper following the same pattern as existing gateways (Tensorix, zAI, Nebius). No new test fixtures were added, consistent with those providers.

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Summary by cubic

Adds TokenMix as a new OpenAI-compatible provider so you can use DeepSeek, Qwen, Kimi, GLM, MiniMax, and more through one endpoint and API key.
Default base is https://api.tokenmix.ai/v1 and default model is deepseek/deepseek-v4-pro.

• New Features
  • Added Tokenmix provider class extending OpenAI with apiBase https://api.tokenmix.ai/v1/ and default model deepseek/deepseek-v4-pro.
  • Registered provider in core/llm/llms/index.ts and packages/openai-adapters (provider union + openAICompatible(...) routing).
  • Added Add-Model GUI tile with API key input and model autodetect via /v1/models.
  • Added docs page and navigation entry for TokenMix configuration.

^{Written for commit 9133615. Summary will update on new commits.}

[github-actions]

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[cubic-dev-ai]

No issues found across 7 files

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