Snake 0.9: crown control via scroll-delta turns (firmware-derived)

README.md

@@ -5,9 +5,21 @@ screen. **32px tiles** (60% larger than 0.7) occupy 89 legal cells of an 11×11
 bounding grid; every tile corner stays inside the actual circle. The square
 board frame is gone. Directional sprite artwork and user icon are preserved. Package identity: `com.ilias.snake`.
 
-**Version 0.8 (versionCode 8): locally tested and release-built; the new features
-still need an on-watch check.** Earlier versions rendered and played on the
-user's Watch S4 41mm. Node tests and numeric layout checks are not device tests.
+**Version 0.9 (versionCode 9): crown control experiment, unit-tested, needs an
+on-watch check.** See docs/CROWN.md for the firmware reasoning.
+
+## Crown control (new in 0.9)
+
+- The watch firmware exposes **no crown event to quickapps**; it routes crown
+  rotation into the scrollable container as scroll deltas. The page is now a
+  full-screen vertical scroll with the dial centered; `onscroll` fires for both
+  crown rotation and finger scroll.
+- Scroll deltas accumulate; every **40 px of scroll = one 90° turn**,
+  clockwise = clockwise turn. Reversals are structurally impossible because
+  turns are relative 90° steps (`rotateDir`-style), never absolute directions.
+- The scroller is snapped back to center after every event, so the board never
+  visibly moves, even though the scroll travel exists.
+- Swipes still work exactly as before; both inputs share the two-slot queue.
 
 ## Play