fix: address the Maps search box by id, and re-prove Phase 5

The Maps omnibox hint rotates: it read "Search here" in the Phase 5 run and
"Try petrol stations, ATMs" in the AUD-128 re-verification, so the recipe's
text match on it failed. The resource id does not rotate.

- internal/ui: add Find/FindID and the "id:" selector; Find dispatches an
  id: selector to the resource id and everything else to text as before.
- internal/recipe: wait/tap/wait_gone/tap_if and the tap helper use Find, so a
  recipe may name a resource id. Guards stay text-only.
- recipes/maps_navigate.recipe: wait/tap id:search_omnibox_text_box.
- tests for the id selector; docs and README updated.

cmd/artemis/main.go

@@ -245,14 +245,14 @@ func cmdDump(r *adb.Runner) error {
 
 func cmdFind(r *adb.Runner, args []string) error {
 	if len(args) != 1 {
-		return fmt.Errorf("usage: artemis find <text>")
+		return fmt.Errorf("usage: artemis find <text|id:resource_id>")
 	}
 	return ensurePhone(r, func() error {
 		h, err := ui.Dump(r)
 		if err != nil {
 			return err
 		}
-		matches := h.FindText(args[0], false)
+		matches := h.Find(args[0], false)
 		if len(matches) == 0 {
 			return fmt.Errorf("no element matching %q", args[0])
 		}