feat: Make the models.dev domain configurable for offline environments
What does this PR do?
There are several issues and pull requests (#8860 #4959 #8830 #8814 #8642 #7313) that discuss the issue that the models.dev domain can't be reached in offline environments. Even if you would use a local Ollama instance, the project tries to fetch https://models.dev/api.json.
The solution I propose is making the models.dev URL configurable, so you can use something in your local network to host the api.json file. A typical corporate environment might have products like Sonatype Nexus Repository that allow for proxying of specific files on the internet. It would be nice if a MODELS_DEV_URL could be configured to contain the path to an internal host with the right files.
How did you verify your code works?
I put my computer in airplane mode, configured the MODELS_DEV_URL environment variable to http://localhost:8000/, ran python3 -m http.server in a directory with api.json, and tried to use a local model.
Fixes: #7313