feat: larger detailed entities — 47 parts, hats, belts, ears

Entities are now ~3x larger and more detailed:

Player (47 parts, was 15):
  - Hat: 3 top + 2 brim (dark purple)
  - Head: 3x2 face (lavender skin)
  - Belt: golden accent across torso
  - Shirt: 3x2 torso + arms out to 3 cells each side
  - Hands: 4 cells (2 per arm, pale lavender)
  - Pants: 3 wide hips + 5 wide legs + split
  - Boots: 3 cells + 2 foot tips (dark purple)
  - half_w=4, half_h=6 (was 2.5x3.5)

Goblin (41 parts):
  - Pointed ears (2 cells)
  - Ragged shirt (green, darker shade)
  - Bare feet (green skin, no boots)
  - Loincloth (dark green)

Auto-constraints: all parts connected to all others (n^2)
  - Simplified from manual constraint lists
  - Works for any template shape
  - Ragdoll will look natural — all parts hold together

macro_rules! p! for compact part definitions
117 tests, 0 failures

tests/edge_cases.rs

@@ -117,9 +117,10 @@ fn player_bodies_count_matches_layout() {
     let mut s = GameSession::new_seeded(42);
     s.init();
     let p = s.get_player().unwrap();
-    assert_eq!(
-        p.body_count, 15,
-        "player should have 15 bodies (profile humanoid)"
+    assert!(
+        p.body_count >= 30,
+        "player should have 30+ bodies (detailed humanoid), got {}",
+        p.body_count
     );
 }