feat(web): keyboard access for search dropdown, combobox fixes (#8079)

* feat(web): keyboard access for search dropdown

Also: fixing cosmetic issue with combobox component.

* fix: revert changing required field

* fix: create new focusChange action

* fix: combobox usability improvements

* handle escape key on the clear button
* move focus to input when clear button is clicked
* leave the dropdown closed if the user has already closed the dropdown and tabs over to the clear button
* activate the combobox if a user tabs backwards onto the clear button

* rename focusChange to focusOutside

* small fixes

* do not activate combobox on backwards tabbing
* simplify classes in "No results" option
* prevent dropdown option from being preselected when clear button is
  clicked

* fix: remove unused event dispatcher interface

web/src/lib/utils/focus-outside.ts

@@ -0,0 +1,21 @@
+interface Options {
+  onFocusOut?: () => void;
+}
+
+export function focusOutside(node: HTMLElement, options: Options = {}) {
+  const { onFocusOut } = options;
+
+  const handleFocusOut = (event: FocusEvent) => {
+    if (onFocusOut && event.relatedTarget instanceof Node && !node.contains(event.relatedTarget as Node)) {
+      onFocusOut();
+    }
+  };
+
+  node.addEventListener('focusout', handleFocusOut);
+
+  return {
+    destroy() {
+      node.removeEventListener('focusout', handleFocusOut);
+    },
+  };
+}