feat: squat rests flat via foot-flat; document ground-lock leveling (L3.1)

Author: a-baran-orhan

packages/posecode-language/src/vocab.ts

@@ -49,7 +49,7 @@ export const KEYWORD_DOCS: Record<string, string> = {
   snap: "Timing mode: fast, near-immediate arrival — an accent.",
   linear: "Timing mode: constant velocity — intentionally mechanical.",
   repeat: "How many times the movement loops.",
-  "ground-lock": "Pins effectors (hands / feet) to the floor for this phase.",
+  "ground-lock": "Pins effectors (hands / feet) to the floor for this phase. Planted feet auto-level flat to the floor unless the ankle is plantarflexed (tiptoe).",
   reach:
     "Drives an effector to a target via ROM-constrained IK: `reach: hand_left ankle_left`, `reach: hands floor`.",
   pin: "Moves the body so an effector sits on an anchor: `pin: hands bar` (hang, pull up, step up, dip).",

spec/examples/squat.posecode

@@ -5,7 +5,6 @@ posecode exercise "Body-weight squat"
   step "Descend" 1.6s settle:
     hips: flex 80
     knees: flex 95
-    ankles: plantarflex 50
     pelvis: hinge 25
     spine: flex 0
     shoulders: flex 70
@@ -16,7 +15,6 @@ posecode exercise "Body-weight squat"
   step "Drive up" 1.2s drive:
     hips: flex 0
     knees: flex 0
-    ankles: plantarflex 0
     pelvis: hinge 0
     spine: flex 0
     shoulders: flex 0