fix(vagrant): legs rotate to walk direction (user preference)

User feedback: 'Beine sollten in die richtung oszillieren, in die
gegangen wird, nicht nach norden/süden relativ zum fenster.'

Old: lower_control.rot = wedge_deg (substrate's body-relative ±30°
sub-angle), legs always oscillated near world-up axis.

New: lower_control.rot = atan(move_x, -move_y) = walk direction in
sprite-top-up convention. Legs visually rotate to align with WASD
direction → stride animation cycles along the walk axis.

Side-effect: 4-direction-anim picker collapsed to single
walk_fwd_lower (the rotation handles directional differentiation;
4 anims kept on disk for later gait-style work). Bumps puppet dep
to 0.4.1 (head south-flick fix).

manifest.module

@@ -15,7 +15,7 @@
         {"id": "lib-core.camera",                 "version": "0.3.0"},
         {"id": "lib-core.render",                 "version": "0.1.0"},
         {"id": "lib-core.maps",                   "version": "0.1.2"},
-        {"id": "lib-core.puppet", "version": "0.4.0"},
+        {"id": "lib-core.puppet", "version": "0.4.1"},
         {"id": "lib-asset.prototype-subterrain",  "version": "0.1.1"}
     ]
 }