Play animation's blend is given in seconds, not in frames of the new animation (#106)

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

src/core/graph/nodes/action/animationNodes.ts

@@ -22,8 +22,8 @@ export const PlayAnimation: NodeDef = {
     'Plays an animation on an object: its rows reach the object and what is placed inside it, so every ' +
     'instance plays on its own. A paused one runs on from where it stands; one already running keeps its ' +
     'frame but wins again over the others on the object. Blend fades numbers and colours over that many ' +
-    'of its frames from what they held when it took over; everything else switches at once.',
-  inputs: [exec(), obj('object'), animationPort(), withDefault(num('blend', 'blend (frames)'), 0)],
+    'seconds from what they held when it took over; everything else switches at once.',
+  inputs: [exec(), obj('object'), animationPort(), withDefault(num('blend', 'blend (s)'), 0)],
   outputs: [exec()],
   params: [],
   run: (_ctx, inputs) => {