Add RodiumAi as a model provider — OpenAI-compatible gateway

[Docteur-Parfait]

Summary

RodiumAi (https://rodiumai.io) is an OpenAI-compatible API gateway that routes requests to models from OpenAI, Anthropic, Google, and other providers through a single API key.

Proposal

Add RodiumAi as a native Continue provider with:

• Provider slug:
  odiumai\
• API base: \https://api.rodiumai.io/v1/\
• Dynamic model listing via \GET /v1/models\
• Catalogue slugs in the form \provider/model\ (e.g. \�nthropic/claude-fable-5, \openai/gpt-5.4)

Why

• Single API key for multiple upstream model families
• OpenAI-compatible interface (extends the existing OpenAI provider pattern used by Groq/Kindo)
• Enables developers to configure RodiumAi from the Add New Model UI

Implementation PR will follow from fork: Rodium-AI/continue