minor improvment on RelatedNotes.svelte:

editor text should be reset on note save

frontend/src/routes/notes/RelatedNotes.svelte

@@ -61,8 +61,9 @@
             let newNote       = await resp.json();
             authors[user.id]  = user;
             notes.push(newNote);
-            note              = {source:'',rendered:''};
             error             = null;
+            note.source       = null;
+            note.rendered     = null;
             return true;
         } else {
             error = await resp.text();