libide/lsp: Add Ide.LspConfigurationItem[] to load-configuration signal
This allows subclasses etc. to react in a reliable manner to the workspace/configuration signal.
The returned variant must be something like aa{sv} and must follow the LSP spec.
Sadly this requires changing from the fancy new LSP thing you did in the GTK4 port to doing it in JS/C again. This would need a lot of effort. One thing I thought that would be at least possible (Whether it is good design is another issue) would be to dlopen itself and check if e.g. some function called $LSPNAME_got_workspace_configuration
exists, but that is something to think of in another MR.
Usage could be e.g. like this: https://github.com/JCWasmx86/GNOME-Builder-Plugins/blob/main/pyright/pyright.vala#L49
Edited by JCWasmx86