Author the machine exercise circuit with props and corrected hip machine motions

Fourteen Planet Fitness machine exercises join the rig library, each with
authored motion, info page, and schematic equipment via the new props layer
(scene shapes, cables, bars, pads) rendered in lockstep by render.py and the
in-app figure renderer. Abductor and Adductor are authored face-on with the
real seated machine motion — knees-bent legs swinging apart/together against
knee pads — replacing the earlier middle-split depiction. The watch target
now bundles the figure renderer and motion rigs too.

Claude-Session: https://claude.ai/code/session_01LEoff8bXGBS83tK1c55Mf7

Workouts/Resources/ExerciseMotions/Leg Raises.info.md

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+# Leg Raises
+
+Lower-ab builder — the slow lowering is the exercise.
+
+- **Category:** Main circuit
+- **Type:** Anti-extension (dynamic)
+- **Targets:** Lower rectus abdominis, hip flexors, deep core
+- **Prescription:** 3 × 8–15 reps, slow negatives
+
+## Setup
+
+**Lying:** flat on your back, legs straight, hands at your sides (or under the
+tailbone to start). **Hanging:** dead hang from a bar, shoulders packed.
+
+## Execution
+
+1. Press the lower back into the floor and brace.
+2. Raise the legs to vertical without bending the knees more than slightly.
+3. Lower *slowly* — 3 seconds or more — stopping before the lower back arches
+   off the floor.
+
+## Cues
+
+- Lower back flat against the floor on lying versions, always.
+- The negative is the rep: lower slower than you lift.
+- Exhale on the way down to keep the ribs from flaring.
+
+## Common Mistakes
+
+- Lower back arching off the floor near the bottom.
+- Dropping the legs instead of lowering them.
+- Using momentum (swinging) on hanging versions.
+
+## Progression
+
+Bent-knee lying raise → straight-leg lying raise → hanging knee raise →
+hanging straight-leg raise → toes-to-bar