Lemenzo Clock v2.5 — premium controls pass

Goal: remove the last obvious stock-Android visual elements without changing app logic.

- Raw Switch controls replaced with Lemenzo blue/navy toggles.
- Spinner rows use custom dark/navy backgrounds, white text and blue outlines.
- Text fields use near-black/navy surfaces with blue outlines and Lemenzo typography.
- App-owned AlertDialogs use dark Lemenzo surfaces and blue action buttons.
- World Clock city picker uses premium navy/blue city rows rather than stock list rows.
- Existing alarm/timer/world/bedtime behavior is unchanged.
- Ringtone picker remains the Android system picker by design.
- Main bottom navigation remains in one Activity with cross-fade.
- All pages retain statusBars + displayCutout + navigationBars safe insets.