Ship the 47-exercise library in-app: export, fixtures, tests, docs

render.py --export bundles the 25 new motion rigs and info pages;
figure-fixtures.json regenerated for all 47 (the Swift solver reproduces
every new motion, including negative-y pins and the new prop uses). The
fixture count assertion moves to 47, and the no-bundled-motion test now
uses Treadmill - a permanent COVERAGE.md exclusion - since Bench Press
exists. 48 tests green; watch target builds. Coverage handoff complete -
TODO-coverage.md retired.

Claude-Session: https://claude.ai/code/session_01HJDQQDA9QdP8zByg43H5v3

Workouts/Resources/ExerciseMotions/Lunge.info.md

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+# Lunge
+
+The split-stance squat — drop the back knee toward the floor, then drive
+back up through the front heel. Bodyweight first, dumbbells in hand later.
+
+- **Category:** Main circuit
+- **Type:** Split-stance squat (bodyweight or dumbbells)
+- **Targets:** Quadriceps, glutes, balance
+- **Prescription:** 3 × 8–10 per side
+
+## Setup
+
+Take a long step so both knees can bend to 90° — front shin vertical,
+back heel up. Hips square to the front, hands at your sides or on hips.
+
+## Execution
+
+1. Lower straight down until the back knee hovers just above the floor.
+2. The front knee stays over the mid-foot, torso upright.
+3. Drive through the front heel to come back up. Finish the set, then
+   switch sides.
+
+## Cues
+
+- Down like an elevator, not forward like a slide.
+- Front heel carries the work; the back leg balances.
+- Squeeze the front glute to stand up.
+
+## Common Mistakes
+
+- Stance too short — the front knee shoots past the toes.
+- Torso pitching forward on the way up.
+- Pushing off the back foot instead of the front heel.
+
+## Progression
+
+Hold a dumbbell in each hand; step backward into each rep (reverse lunge)
+or elevate the back foot for a split squat.