feat(puppet): v0.4.4 — set_play_speed(handle, anim_id, speed) API

New public function to change the play-speed of a currently-playing
animation WITHOUT resetting its cycle position. Calling M.play with a
new speed sets t=0, causing visible cycle restart; set_play_speed
mutates only the speed field.

Use case: sprint toggle mid-walk doubles walk-anim cadence smoothly.
Silent no-op when the anim is not currently playing.

manifest.lib

@@ -1,6 +1,6 @@
 {
     "id": "lib-core.puppet",
-    "version": "0.4.3",
+    "version": "0.4.4",
     "api_min": "0.1",
     "deps": []
 }