🐛 Hotfix 2.4.1: distance sorting, search text, native ad media

[ngapp-dev]

Summary

🧭 Distance sorting is back

• "Distance" is selectable again in the stations sort dialog and is saved in preferences (it was silently mapped to "Name").
• Stations are sorted by distance in the repository, since only it knows the user's position. Ascending and descending both work, the list re-sorts when the location changes, and stations with an unknown distance go last.
• The DAO orders by title for distance sorting too, so the list stays stable while the location is unknown (it was ordered by NULL).
• Fix: distanceInKm returned NaN when the user stands exactly at a station (rounding pushed the cosine past 1), which would show "NaN km" and break the sort.

🔍 Invisible search text

• The search field drew its text with colorScheme.onBackground. In this palette that is the background/card color (white in the light theme, dark in the dark theme), so typed text vanished in both themes. It now uses the typography's text color. All search screens share this field.

📢 AdMob native ad media view

• When an AdMob ad had an icon, the row showed the icon in a 74x66 thumbnail and hid the registered MediaView. The AdMob validator reported it as 0x0: "media views smaller than 120x120 will be demonetized".
• The thumbnail is now always the ad's media at 120x120, as it already was for Yandex. The icon moves to the small slot next to the "Ad" label. Android and iOS.

🔖 Version

• Android 2.4.0 → 2.4.1 (versionCode 2401).
• iOS 1.1.0 (3) → 1.1.1 (4), app and widget extension.

Review notes

• Users who never changed the station sorting now get distance by default, because DISTANCE = 0 is the proto default.
• AdMob rows with an icon are now taller than a regular list row; the 120x120 media minimum requires it.
• Verified on the Android emulator: distance order, search text in light and dark themes, AdMob validator "No implementation issues found". The iOS app builds; not checked on a device.
• Tests: distance sorting (asc, desc, unknown location, re-sort on a location change), DAO fallback order, the NaN case.