Generate 3.18.0 types

[predragnikolic]

This PR brings 3.18 LSP types.

I had the false impression that the latest changes to metaModel.json file are done at microsoft/vscode-languageserver-node, but actually the latest chnages are done at microsoft/language-server-protocol,
so I updated the download script to point to microsoft/language-server-protocol

I also manually edited lsp.json to add diagnostic message union string MarkupContent
until they fix it upstream.

As Janos noticed they have added the type in microsoft/language-server-protocol@df7c77b
and later removed it in microsoft/language-server-protocol@7e1b69d (I have asked them if this was a mistake)

[rchl]

This doesn't seem to match https://microsoft.github.io/language-server-protocol/specifications/lsp/3.18/specification/#textDocument_colorPresentation and also it would be a breaking change.

EDIT: I suppose breaking changes like that are allowed in new spec versions. Technically those should already be guarded by capability.

[rchl]

Will assume that someone forgot to update the html version of the spec.

[jwortmann]

There was a discussion about that in microsoft/language-server-protocol#2235 with some backlash due to it being a breaking change.

But even if it ends up in the specs, our code should be fine because we already handle this case:
https://github.com/sublimelsp/LSP/blob/40c9fe32ad0d4edf084e19b21e71505796c12dcd/plugin/color.py#L32-L34

https://github.com/sublimelsp/LSP/blob/40c9fe32ad0d4edf084e19b21e71505796c12dcd/plugin/session_buffer.py#L570-L571

[jwortmann]

I had the false impression that the latest changes to metaModel.json file are done at microsoft/vscode-languageserver-node, but actually the latest chnages are done at microsoft/language-server-protocol,

According to microsoft/language-server-protocol#2235 (comment) changes often get ported from microsoft/vscode-languageserver-node to microsoft/language-server-protocol. But it also seems more appropriate to me to use microsoft/language-server-protocol as the source for the metaModel.json file, because that is the official specs repo, so in theory that should increase the probability that the metaModel.json matches the specs documentation.

[jwortmann]

We forgot to also (manually) update the DiagnosticClientCapabilities.

There is a new property markupMessageSupport in the 3.18 specs, which seems also not be in the metaModel.json anymore.