nos serve: Serve optimized nos model by name

[spillai]

• nos serve -m stability-ai/stable-diffusion-v2: Serve optimized nos model (blocking)
• nos serve -d stability-ai/stable-diffusion-v2: Serve optimized `nos model (daemon/detached)
• nos serve -c deployment.yml: Serve collection of models (blocking)
• nos serve -d -c deployment.yml: Serve collection of models (daemon/detached)