Support toplevel module definition hover (#44)

Co-authored-by: Cristiano Calcagno <cristianoc@users.noreply.github.com>

Author: amiralies

src/rescript-editor-support/Hover.re

@@ -56,6 +56,7 @@ let newHover = (~rootUri, ~file: SharedTypes.file, ~getModule, loc) => {
   | TypeDefinition(name, decl, _stamp) =>
     let typeDef = Shared.declToString(name, decl);
     Some(codeBlock(typeDef));
+  | LModule(Definition(stamp, _tip))
   | LModule(LocalReference(stamp, _tip)) =>
     let%opt md = Hashtbl.find_opt(file.stamps.modules, stamp);
     let%opt (file, declared) =
@@ -80,7 +81,7 @@ let newHover = (~rootUri, ~file: SharedTypes.file, ~getModule, loc) => {
       | None => file.moduleName
       };
     showModule(~name, ~file, declared);
-  | LModule(_) => None
+  | LModule(NotFound) => None
   | TopLevelModule(name) =>
     let%opt file = getModule(name);
     showModule(~name=file.moduleName, ~file, None);