fix(frame): make the ROTATE strip behave on switching parameters

Four follow-ups on the strip added for the quarter turns / straighten / AUTO.

AUTO is "snap to the sensor horizon": it now drops the manual STRAIGHTEN offset when it is switched on, so enabling it after a hand-set angle really levels the photo instead of leaving the angle untouched (the chip goes from "ROTATE 0 · +22°" to "ROTATE · AUTO").

The "<" back button on a slider row returns to the strip the row was opened from (STRAIGHTEN to ROTATE, COLOR TEMP to TEMP) instead of closing everything, and picking another parameter — a frame chip or the global RESET — closes the open row, so the straighten slider no longer outlives the parameter it belongs to.

Opening another photo from the library resets the turn, the fine straighten angle and AUTO with it: a new photo starts level.

App.tsx

@@ -857,7 +857,12 @@ export default function App() {
     if (!result.canceled && result.assets && result.assets.length > 0) {
       const asset = result.assets[0];
       setLibraryImageUri(asset.uri);
+      // A new photo starts level: the previous photo's turn, fine straighten
+      // and AUTO horizon must not carry over.
       setPhotoRotation(0);
+      setPhotoStraighten(0);
+      setAutoHorizon(false);
+      setHorizonRoll(0);
       setMode('library');
       // Picking from the camera is the other half of that switch (the camera
       // button is the way back), so the camera's edits must not land on the