Add native viewing support for jsonl/ndjson

[timkpaine]

References

jsonlines / ndjson have traction (some examples lazily collected from the web, shopify, duckdb).

Since the differences are very trivial wrt existing json support, it isn't really worth it to defer this functionality to e.g. a community extension.

Code changes

Register jsonl and ndjson file types, and corresponding mime types. NOTE: standardization is trailing utilization, so it is messier than one would prefer.
ndjson/ndjson-spec#35
wardi/jsonlines#22

Then tweak the JSON extension to convert jsonl to json when the mime type is that of jsonl.

User-facing changes

.jsonl and .ndjson files will now appear as json files and open in the default json opener.

Backwards-incompatible changes

None. May effect existing mime render extensions for jsonl and ndjson, if these exist.

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[fcollonval]

Thanks @timkpaine I targeted this to 4.0.0 to discuss on Wednesday weekly call to see if we accept this as late addition (we have release RC so no promise). Otherwise it will need to move on 4.1.0.

[krassowski]

If we delay merging this PR until 4.1, is there a chance these would be standardized by then, or is it not worth waiting for it?

[timkpaine]

not worth waiting, i doubt this will be standardized soon

[sp4ce]

Hi, I am working on helping to standardize application/jsonl MIME_TYPE, but I have no experience in doing so, so I confirm it will take me a bit of time to write the RFC and submit it, so it's not worth waiting.

[fcollonval]

The consensus at the dev meeting was too push this to 4.1.0

[fcollonval]

I'll rebase this PR on main as we branch out 4.0.x to be able to merge 4.1 feat in main.

[fcollonval]

Thanks @timkpaine