Add a local `tv-search` Expo module that hosts SwiftUI's `.searchable`
in a UIHostingController (adapted from expo-tvos-search, minus its native
results grid). It emits typed text to React Native so the existing search
pipeline and custom TV results grid are reused. Handles the RN-tvOS remote
gesture release needed for keyboard input on device.
Wire it into TVSearchPage as a sticky header above the scrollable results,
with a TVFocusGuideView bridge so focus can move from the tab bar into the
native search field.
