Request textDocument/hover from all configured language servers

[tcoopman]

I couldn't find if this is an issue with the event system (#8021), and can't seem to find a similar issue.

onHover docs doesn't work well with multiple LSPs. For example, I've got both ["tailwind", "elixir"] configured.
If I hover on something from elixir, I don't get any docs. If I remove the tailwind lsp, I do get docs for elixir, but of course none for the tailwind classes.
If I reverse the order, hover on elixir works but not on tailwind.

So the issue is that hover should work for both configured lsps.

Discussed in #8872

[kirawi]

helix/helix-term/src/commands/lsp.rs

Lines 1279 to 1328 in 5109286

	pub fn hover(cx: &mut Context) {
	let (view, doc) = current!(cx.editor);
	// TODO support multiple language servers (merge UI somehow)
	let language_server =
	language_server_with_feature!(cx.editor, doc, LanguageServerFeature::Hover);
	// TODO: factor out a doc.position_identifier() that returns lsp::TextDocumentPositionIdentifier
	let pos = doc.position(view.id, language_server.offset_encoding());
	let future = language_server
	.text_document_hover(doc.identifier(), pos, None)
	.unwrap();
	cx.callback(
	future,
	move |editor, compositor, response: Option<lsp::Hover>| {
	if let Some(hover) = response {
	// hover.contents / .range <- used for visualizing
	fn marked_string_to_markdown(contents: lsp::MarkedString) -> String {
	match contents {
	lsp::MarkedString::String(contents) => contents,
	lsp::MarkedString::LanguageString(string) => {
	if string.language == "markdown" {
	string.value
	} else {
	format!("```{}\n{}\n```", string.language, string.value)
	}
	}
	}
	}
	let contents = match hover.contents {
	lsp::HoverContents::Scalar(contents) => marked_string_to_markdown(contents),
	lsp::HoverContents::Array(contents) => contents
	.into_iter()
	.map(marked_string_to_markdown)
	.collect::<Vec<_>>()
	.join("\n\n"),
	lsp::HoverContents::Markup(contents) => contents.value,
	};
	// skip if contents empty
	let contents = ui::Markdown::new(contents, editor.syn_loader.clone());
	let popup = Popup::new("hover", contents).auto_close(true);
	compositor.replace_or_push("hover", popup);
	}
	},
	);
	}