feat: get running models

[vansangpfiev]

issue: https://github.com/janhq/cortex/issues/589
endpoint: v1/models
response example:

{
    "data": [
        {
            "id": "nomic-embed-text-v1.5.f16",
            "object": "model"
        },
        {
            "id": "mistral-7b-instruct-v0.1.Q4_0",
            "object": "model"
        }
    ],
    "object": "list"
}

bump cortex.llamacpp version to support this: v0.1.9

[louis-jan]

LGTM