Add array search params

[fehnomenal]

This is an alternative to #583, where the user can decide whether the array elements should be joined or each have their own occurrence in the search params.

This adds a new option to the explicit search param definition: joinArray. It controls whether .join(',') gets appended in the generated call of the appendSp function.
Otherwise the array gets passed as it is and is turned into many parameters.

fix #580

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Side-note: Have you considered not exporting the appendSp string but the function? It would keep the diff smaller if ROUTES.ts would import it from the lib 😅

[jycouet]

I kinda like the fact that there is 0 import from the lib 🤣
Yes, diffs are big, like this you take a lot of contribution 😉

[fehnomenal]

Phew, this was harder than expected as we do not know if we have an array during the code generation step. So the "logic" to join has to run always. But that does not work correctly if the value is undefined (String(undefined) => 'undefined').

Let me know what you think!

[jycouet]

Great job 💪
Few questions and we are good I think ✅

[jycouet]

It needs a changeset and we are good.
Thx for your work.

Let me know if you want to finish it, if not, I can take it from here.

[jycouet]

It should be

StringOrUndefined(params?.limit),

no?

[fehnomenal]

params is definitively set in line 60. I struggled so long to get the ?. operator to bet used in the correct places 😅

[fehnomenal]

I used minor for the changeset. Is this correct in pre mode?

[jycouet]

@all-contributors please add @fehnomenal for code

Thx a lot

[allcontributors]

@jycouet

I've put up a pull request to add @fehnomenal! 🎉