web: improve testability (#6952)

web/improve testability

This is a trio of small hacks that allow the E2E tests to find several components
on the page while the test is running:

- Add a `data-managed-for` field to SearchSelect's positioned elements. If a search
  has a `name` field, it will be reflected here, allowing tests to find specific
  instances of the dropdown elements.
- Add a forwarder to the search select wrappers we use for our SearchSelect.
- Added aria details to the UserLibrary header to make it easy to identify.

web/src/elements/forms/SearchSelect.ts

@@ -134,6 +134,9 @@ export class SearchSelect<T> extends CustomEmitterElement(AKElement) {
         super.connectedCallback();
         this.dropdownContainer = document.createElement("div");
         this.dropdownContainer.dataset["managedBy"] = "ak-search-select";
+        if (this.name) {
+            this.dropdownContainer.dataset["managedFor"] = this.name;
+        }
         document.body.append(this.dropdownContainer);
         this.updateData();
         this.addEventListener(EVENT_REFRESH, this.updateData);