Atualizar forma de instalação do FastAPI para se adequar a versão 0.112

[rennerocha]

A versão 0.112.0 alterou os pacotes instalados (uma breaking change). Agora é necessário instalar o fastapi[standard] para ter acesso ao CLI: https://fastapi.tiangolo.com/release-notes/#01120

Se seguirmos apenas as instruções existentes, teremos o seguinte erro:

(fast-zero-py3.12) ➜  fast_zero fastapi dev fast_zero/app.py 
To use the fastapi command, please install "fastapi[standard]":

	pip install "fastapi[standard]"

Traceback (most recent call last):
  File "/home/renne/.cache/pypoetry/virtualenvs/fast-zero-Ym0yTX-Z-py3.12/bin/fastapi", line 8, in <module>
    sys.exit(main())
             ^^^^^^
  File "/home/renne/.cache/pypoetry/virtualenvs/fast-zero-Ym0yTX-Z-py3.12/lib/python3.12/site-packages/fastapi/cli.py", line 12, in main
    raise RuntimeError(message)  # noqa: B904
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^
RuntimeError: To use the fastapi command, please install "fastapi[standard]":

	pip install "fastapi[standard]"