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/Incline Bench Press/motion.json

@@ -0,0 +1,40 @@
+{
+  "name": "Incline Bench Press",
+  "primary": 1,
+  "camera": {"zoom": 0.85},
+  "working": ["arm_r", "arm_l"],
+  "props": [
+    {"type": "scene", "shapes": [
+      {"kind": "line", "pts": [[142, 127], [86, 60]], "w": 9, "depth": 8},
+      {"kind": "line", "pts": [[140, 130], [166, 127]], "w": 8, "depth": 8},
+      {"kind": "line", "pts": [[152, 133], [152, 150]], "w": 5}
+    ]},
+    {"type": "bar", "at": ["hand_r", "hand_l"], "halfLen": 26, "plateR": 12}
+  ],
+  "frames": [
+    {
+      "hold": 0.4, "tween": 0.9,
+      "root": {"pos": [148, 122], "pitch": -38},
+      "spine": [0, 0],
+      "neck": 18, "head": -4,
+      "shoulder_r": 30, "elbow_r": 115,
+      "shoulder_l": 30, "elbow_l": 115,
+      "hip_r": 85, "knee_r": 75, "ankle_r": 5,
+      "hip_l": 85, "knee_l": 75, "ankle_l": 5,
+      "pins": {"foot_r": [198, 148], "foot_l": [202, 150],
+               "hand_r": [106, 38], "hand_l": [110, 40]}
+    },
+    {
+      "hold": 0.4, "tween": 1.2,
+      "root": {"pos": [148, 122], "pitch": -38},
+      "spine": [0, 0],
+      "neck": 18, "head": -4,
+      "shoulder_r": 118, "elbow_r": 5,
+      "shoulder_l": 118, "elbow_l": 5,
+      "hip_r": 85, "knee_r": 75, "ankle_r": 5,
+      "hip_l": 85, "knee_l": 75, "ankle_l": 5,
+      "pins": {"foot_r": [198, 148], "foot_l": [202, 150],
+               "hand_r": [98, -3], "hand_l": [102, -1]}
+    }
+  ]
+}