Add STORE_MODEL_IN_DB to LiteLLM environment variables

[lumoe]

Changes

• Add the STORE_MODEL_IN_DB variable to the LiteLLM template. This flag is required in order to save models and API keys to the database. Not saving them defeats the purpose of using the LiteLLM proxy.

Configuration docs for LiteLLM: https://docs.litellm.ai/docs/proxy/config_settings

[lumoe]

Fixes the error message Failed to add model: Error: {'error': "Set 'STORE_MODEL_IN_DB='True' in your env to enable this feature."}

[github-actions]

Hi @lumoe! 👋

It appears to us that you are either adding a new service or making changes to an existing one.
We kindly ask you to also review and update the Coolify Documentation to include this new service or it's new configuration needs.
This will help ensure that our documentation remains accurate and up-to-date for all users.

Coolify Docs Repository: https://github.com/coollabsio/coolify-docs
How to Contribute a new Service to the Docs: https://coolify.io/docs/get-started/contribute/service#adding-a-new-service-template-to-the-coolify-documentation

[lumoe]

A link to the docs for the LiteLLM proxy is already present in the coolify docs, no changes are required.