[lana-20]

Fixes #329.

wait and scroll-to walked up to the nearest mapped ancestor. For a plain text in a list, that was the list, and its ref tapped the list's center. The walk now stops at a list, unless the list is what matched. The match comes back with no ref, as find reports it:

testid=dialogOutcome is visible after 408ms — (no ref) nothing yet [42,651][1038,708]

This takes the issue's open choice: wait_for returns an element with an empty ref, not None. That also applies to plain text outside a list, so docs/guides/cli.md has new output.

Other changes:

• A no-ref answer is labeled by uitree.Describe, as map labels: cleaned, bounded, never a password. find shares it.
• app_scroll_to is listed as device text under --mark-device-text.
• An element with no ref prints with no leading space in Python, Java and .NET. All five clients document the empty ref.

Measured

A sweep waited on the first 14 visible texts of each screen:

	main	This PR
Android 15 emulator	22 answers were the list	0 of 203, 9 apps
iOS 26.5 simulator	18 answers were the list	0 of 193, 8 apps

The main runs covered only MobiumApp, plus Settings on iOS. They show the sweep can catch the defect, and are not a like-for-like count. The apps include Compose, SwiftUI, Flutter and third-party ones.

All five clients and MCP took the empty ref on the Android emulator. A new section of wait-states.sh fails on main on both devices and passes here. locators, feed and mobium-app pass on both, and test-runner on Android.

Not run on a real phone.