Update 055

[maxDavid40]

• Update the documentation about /v2/tokenizer and /v2/decode missing in previous PR
• Change metrics routes init in declare_application (use mounts_metrics function from vllm)
• Update required attributes to init AsyncEngineRPCServer (rpc_path)
• Update required attributes to serve_http function (engine)
• Update package in pyproject.toml and requirements.txt
• Fix some docstrings