CLDR-16844 Preliminary refactoring for Dashboard

-New module cldrDashContext.mjs, mostly code moved from cldrGui.mjs

-Encapsulate some constant strings such as OPEN_DASH_BUTTON_CLASS

-Rename cldrDash.mjs to cldrDashData.mjs for clarity

-Rename TestCldrDash.mjs to TestCldrDashData.mjs

-Remove unused parameter tr from cldrTable.getSingleRowUrl

-Remove some debugging console.log calls from DashboardWidget.vue

-Comments

tools/cldr-apps/js/src/views/OverallErrors.vue

@@ -22,7 +22,7 @@ const errors = ref(null);
 const locale = ref(getCurrentLocale());
 
 async function loadData() {
-  const resp = getLocaleErrors(locale.value);
+  const resp = await getLocaleErrors(locale.value);
   if (!resp || !resp.body) {
     errors.value = null;
   } else {