[ENHANCEMENT] Add query param 'metadata_only' on almost all query endpoints

[Nexucis]

This PR is introducing the query param metadata_only on every endpoint excepting the datasource one.

On the datasource endpoint, the query param default and kind are used to filter the list. But for that we need to have access to the spec.

On the home page, when it's loading ~1k dashboards, it takes around 3s to load. With this PR it's taking 500ms.

[celian-garcia]

Let's open the debate that we all expect: should it be metadata_only or something else?

Food for think:
What if the default was to actually give only the metadata to prevent from dumb requests. You could have full=true for example in all the queries that actually want details

[Gladorme]

partial, full, skip_spec, ignore_spec, ...
Depends on the the default behavior too, "full=true" will not work with the current implem

[celian-garcia]

Yes that's what I'm saying. Changing the default behaviour to by default having full=false would in a sense give a message that if you use full=true you don't use default and don't complain if it fails or take time to answer, or is paginated.

[Nexucis]

When you get the list of data with no query parameter, you won't expect a partial response data.
What we can do is to provide a pagination so you cannot get everything excepting if you explicitly say it.

metadata_only is at least explicitly saying you will only get the metadata and nothing else.

[Nexucis]

but before including a pagination, I want to make everything to be able to get all data without crashing Perses.

[celian-garcia]

Okay, just wanted to make sure we explore all the possibilities.

I think I'd tend to be in favor of an API that by default gives everything and light than something very detailed and potentially paginated in the future. But at the end as long as the light mode is available I'm good with any of the default behaviour.

[nicolastakashi]

Pagination for the win 👍🏽

[Gladorme]

Let's make UI functions more generic so we can request whatever we want + add api e2e tests with query param

[Gladorme]

🚀