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/Dumbbell Bench Press.info.md

@@ -0,0 +1,38 @@
+# Dumbbell Bench Press
+
+The dumbbell press on the flat bench — a deeper, freer pressing arc than
+the bar, one weight in each hand.
+
+- **Category:** Main circuit
+- **Type:** Free-weight horizontal press (dumbbells)
+- **Targets:** Chest, front delts, triceps
+- **Prescription:** 3 × 8–12
+
+## Setup
+
+Sit with the dumbbells on your thighs, then lie back and kick them up to
+straight arms over the shoulders. Feet flat, shoulder blades pinched.
+
+## Execution
+
+1. Lower both dumbbells to the outside of the chest, elbows about 45°
+   from the body.
+2. Reach a comfortable stretch — deeper than a bar allows.
+3. Press back up and slightly together to lockout.
+
+## Cues
+
+- The dumbbells travel in a shallow A-shape, not straight lines.
+- Keep the wrists neutral and stacked over the elbows.
+- Lower slowly; the stretch is where dumbbells earn their keep.
+
+## Common Mistakes
+
+- Clanging the weights together at the top.
+- Uneven pressing — one side racing ahead.
+- Dropping the dumbbells from lockout instead of walking them down.
+
+## Progression
+
+Add weight while both sides press evenly; pause reps in the stretch
+position.