Register `SUPPORTED_DRIVER_TYPES["uiautomator2"]` backed by the new
`AndroidDriver`, mirroring `WDADriver` method-for-method. tap/swipe/home use
the confirmed UiAutomator2 mobile commands (`clickGesture`, `dragGesture`,
`pressKey`); swipe converts `duration_ms` to a drag speed with a zero-distance
guard. Adds 34 mocked unit tests, an env-var-gated integration test, and
corrects the outdated "Android not registered" note in the iPhone setup doc.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
