Refactor: Use multi-index search for meili

[almostSouji]

Can potentially avoid having multiple split commands to query docs in favor of a global search. (Potential issues with key length limited by custom id, maybe re-consider command setup)

[almostSouji]

Unsure how to handle versions, the website seems to know which sub packages need to be queried at which version
So the version dropdown would then follow the discord.js version

Also arises the question of if we need sub commands at all or if this can be a one and done solution
Imo this depends on how the version dropdown may work, we can declare specific versions of subpackages as unsupported (people may always use the website to link to directly), as the general use case for the docs app seems to be the main package in the currently supported version range with occasional expanding search into subpackages relevant to the same range.

[almostSouji]

From the api.json, it has a dependencies: field listing the packages and their versions. I would have to look up where that is in the split json though. I believe it‘s a seperate dependencies.json or so https://github.com/discordjs/discord.js/blob/48a9c665dedf9f5085a7992df3a87de3bca2301a/packages/scripts/src/generateSplitDocumentation.ts#L1023 it’s in .dependencies.api.json