feat: Begins migrating views from leaf to elementary

Sources/App/Views/Buttons.swift

@@ -0,0 +1,9 @@
+import Elementary
+
+struct ToggleFormButton: HTML {
+  var content: some HTML<HTMLTag.a> {
+    a(.href("javascript:void(0)"), .on(.click, "toggleContent('form')"), .class("btn-add")) {
+      "+"
+    }
+  }
+}