🚀 Describe the new functionality needed

/admin API will contain routes that are designated to be administrative tasks and not exposed to all users. The admin API will expose things like stack mutation, inspection, etc.

This feature tracks the creation of:

• the API stub
• its routing layer
• log level
• potentially the migration of routes like /providers and /inspect.

💡 Why is this needed? What if we don't build it?

Having all routes exposed to users limits the surface we can expose and causes the stack, and its persona, to be unclear to users. having a clear delineation between user facing API and administrative APIs offers a clear path forward for the personas of Llama Stack.

Other thoughts

No response