fix(navigation): preserve user transitions across directional navigation

src/primitives/Column.tsx

@@ -34,7 +34,6 @@ export const Column: Component<ColumnProps> = (props) => {
     <view
       transitionUp={defaultTransitionUp}
       transitionDown={defaultTransitionDown}
-      transition={/* @once */ {}}
       {...props}
       onUp={/* @once */ chainFunctions(props.onUp, onUp)}
       onDown={/* @once */ chainFunctions(props.onDown, onDown)}

src/primitives/Row.tsx

@@ -33,7 +33,6 @@ export const Row: Component<RowProps> = (props) => {
     <view
       transitionLeft={defaultTransitionBack}
       transitionRight={defaultTransitionForward}
-      transition={/* @once */ {}}
       {...props}
       selected={props.selected || 0}
       onLeft={/* @once */ chainFunctions(props.onLeft, onLeft)}

src/primitives/Virtual.tsx

@@ -540,7 +540,6 @@ function createVirtual<T>(
 
   return (
     <view
-      transition={/* @once */ {}}
       transitionLeft={isRow ? defaultTransitionBack : undefined}
       transitionRight={isRow ? defaultTransitionForward : undefined}
       transitionUp={!isRow ? defaultTransitionUp : undefined}

src/primitives/utils/handleNavigation.ts

@@ -117,32 +117,41 @@ export const navigableForwardFocus: lng.ForwardFocusHandler = function () {
   return selectChild(navigable, selected);
 };
 
+type NavWithTransitionCache = lngp.NavigableElement & {
+  _navBaseTransition?: object;
+  _navLastMerged?: object;
+};
+
 export function handleNavigation(
   direction: 'up' | 'right' | 'down' | 'left',
 ): lng.KeyHandler {
   return function () {
-    const el = this as lngp.NavigableElement;
-    const transition =
+    const el = this as NavWithTransitionCache;
+    const directional =
       direction === 'up'
         ? el.transitionUp
         : direction === 'down'
           ? el.transitionDown
           : direction === 'left'
             ? el.transitionLeft
-            : direction === 'right'
-              ? el.transitionRight
-              : undefined;
+            : el.transitionRight;
 
-    if (transition) {
-      const currentTransition =
+    if (directional) {
+      const current =
         typeof el.transition === 'object' && el.transition !== null
           ? el.transition
           : {};
 
-      el.transition = {
-        ...currentTransition,
-        ...(transition as object),
-      };
+      // Re-snapshot the developer-supplied transition whenever el.transition
+      // doesn't match our last merge — that means it was set externally
+      // (initial render or a reactive update), not by this handler.
+      if (current !== el._navLastMerged) {
+        el._navBaseTransition = current;
+      }
+
+      const merged = { ...(directional as object), ...el._navBaseTransition };
+      el.transition = merged;
+      el._navLastMerged = merged;
     }
 
     return moveSelection(