The `lsp.servers.<name>` option description links to the server's
homepage if it can evaluate the default package's `meta.homepage`.
However, users may evaluate this description, e.g. when building NixOS
docs with `documentation.nixos.includeAllModules`. Further, users may
have a different nixpkgs revisions to ours. Therefore, we need to allow
for the package not being in nixpkgs.
Since `mkPackageOption` will throw in the default, we can catch it with
`tryEval`.
- Re-implement setup wrapping and capabilities to preserve existing
behaviour
- Alias `package` options to new lsp module
- Alias `packageFallback` options to new lsp module
- Alias `preConfig` and `postConfig` to `lsp.luaConfig`
