Inference to use provider resource id to register and validate (#428)

This PR changes the way model id gets translated to the final model name
that gets passed through the provider.
Major changes include:
1) Providers are responsible for registering an object and as part of
the registration returning the object with the correct provider specific
name of the model provider_resource_id
2) To help with the common look ups different names a new ModelLookup
class is created.



Tested all inference providers including together, fireworks, vllm,
ollama, meta reference and bedrock

llama_stack/providers/inline/eval/meta_reference/eval.py

@@ -150,7 +150,7 @@ class MetaReferenceEvalImpl(Eval, EvalTasksProtocolPrivate):
                     messages.append(candidate.system_message)
                 messages += input_messages
                 response = await self.inference_api.chat_completion(
-                    model=candidate.model,
+                    model_id=candidate.model,
                     messages=messages,
                     sampling_params=candidate.sampling_params,
                 )