Change root path for API to display an informative landing message/page

[alyssadai]

Currently, navigating to the root of the API (/) displays a {"detail": "not found"} message by default.

We want to update our path config in FastAPI to instead show a page that displays a simple welcome message and directs users to visit the API docs for more information should be sufficient, e.g.:

Welcome to the Neurobagel REST API!

Please visit the documentation at /docs to view available API endpoints.

(If /docs part could be made a link to the <base-url>/docs, that would also be cool but is not a necessity.)

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[samadpls]

Hi @alyssadai , can i work on this task :)

[alyssadai]

Hi @samadpls, we'd be happy for you to open a PR!

I've updated the issue description with a bit more detail on what we're looking for. Feel free to let me know if further clarification is needed.

[surchs]

🚀 Issue was released in v0.2.0 🚀