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/Push-Up/info.md

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+# Push-Up
+
+The bodyweight press — a moving plank: lower the chest to the floor and
+press back up without the hips sagging.
+
+- **Category:** Warm-up and main circuit
+- **Type:** Bodyweight horizontal press
+- **Targets:** Chest, front delts, triceps, trunk
+- **Prescription:** 3 × 8–15
+
+## Setup
+
+Hands under the shoulders, legs long, toes tucked. Squeeze the glutes
+and brace so the body is one straight line from head to heels.
+
+## Execution
+
+1. Bend the elbows about 45° from the body and lower the chest toward
+   the floor.
+2. Stop a fist's height off the ground, body still one line.
+3. Press the floor away to straight arms.
+
+## Cues
+
+- The plank never breaks — hips neither sag nor pike.
+- Screw the hands into the floor to keep the elbows tracking.
+- Chest leads the descent, not the chin or the hips.
+
+## Common Mistakes
+
+- Hips sagging into a banana shape.
+- Flaring the elbows to 90°.
+- Craning the neck at the floor.
+
+## Progression
+
+Start from an incline (hands on a bench) if reps stall; graduate to feet
+elevated, then slow negatives.