Add the free-weight canon and bodyweight staples (16 exercises)

Squat/lunge: Barbell Squat, Goblet Squat, Bodyweight Squat, Lunge.
Bench station: Bench Press, Incline Bench Press, Dumbbell Bench Press,
Dumbbell Fly (the fly authors the face-on camera for its frontal arc).
Dumbbell rack: Dumbbell Row, Dumbbell Shoulder Press, Dumbbell Curl,
Lateral Raise - first uses of the dumbbell prop. Bodyweight: Push-Up,
Pull-Up, Crunch, Dip.

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

Exercise Library/Dumbbell Row/info.md

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+# Dumbbell Row
+
+The one-arm row — knee and hand braced on the bench, pull the dumbbell
+from a dead hang to the ribs.
+
+- **Category:** Main circuit
+- **Type:** Free-weight horizontal pull (dumbbell)
+- **Targets:** Lats, mid-back, biceps
+- **Prescription:** 3 × 8–12 per side
+
+## Setup
+
+Put the same-side knee and hand on a bench, the other foot planted on
+the floor. Back flat and parallel to the ground, dumbbell hanging
+straight down from the shoulder.
+
+## Execution
+
+1. Pull the dumbbell up and back toward the hip until the elbow passes
+   the ribs.
+2. Squeeze the shoulder blade at the top.
+3. Lower to a full hang and stretch. Finish the set, then switch sides.
+
+## Cues
+
+- The elbow leads; the hand just holds on.
+- Shoulders stay square to the floor — no twisting to hoist the weight.
+- Long neck, eyes down; the back stays flat.
+
+## Common Mistakes
+
+- Rotating the torso open at the top of each rep.
+- Pulling with the biceps instead of driving the elbow back.
+- Cutting the stretch short at the bottom.
+
+## Progression
+
+Heavier dumbbells while the torso stays quiet; pause each rep at the top
+for a stricter mid-back stimulus.