Plugin names are not prefixed with the package name

[krassowski]

Something which came up in jupyterlab/jupyterlab#16082: jupyter-ai plugin names like:

jupyter-ai/packages/jupyter-ai/src/index.ts

Line 29 in 144cc9b

id: 'jupyter_ai:plugin',

are not prefixed with the package name:

jupyter-ai/packages/jupyter-ai/package.json

Line 2 in 144cc9b

"name": "@jupyter-ai/core",

Nothing bad in itself, but since users appear to expect jupyter labextension disable @jupyter-ai/core to work maybe it is worth changing to follow the practice used by all other core extensions (and many third party-extensions too).