Flexible race system with slot-based equipment and dragon race

- Expand race TOML schema: 7 stats, body shape (size/weight/custom slots),
  natural armor and attacks with damage types, resistances, traits/disadvantages,
  regen multipliers, vision types, XP rate, guild compatibility
- Replace equipped_weapon/equipped_armor with slot-based HashMap<String, Object>
- Each race defines available equipment slots; default humanoid slots as fallback
- Combat uses natural weapons/armor from race when no gear equipped
- DB migration from old weapon/armor columns to equipped_json
- Add Dragon race: huge body, custom slots (forelegs/wings/tail), fire breath,
  natural armor 8, fire immune, slow XP rate for balance
- Update all existing races with expanded fields (traits, resistances, vision, regen)
- Objects gain optional slot field; kind=weapon/armor still works as fallback
- Update chargen to display race traits, size, natural attacks, vision
- Update stats display to show equipment and natural bonuses separately
- Update TESTING.md and AGENTS.md with race/slot system documentation

Made-with: Cursor

src/bin/mudtool.rs

@@ -114,8 +114,7 @@ fn cmd_players(db: &SqliteDb, args: &[String]) {
                     println!("  Room: {}", p.room_id);
                     println!("  Admin: {}", p.is_admin);
                     println!("  Inventory: {}", p.inventory_json);
-                    if let Some(ref w) = p.equipped_weapon_json { println!("  Weapon: {w}"); }
-                    if let Some(ref a) = p.equipped_armor_json { println!("  Armor: {a}"); }
+                    println!("  Equipped: {}", p.equipped_json);
                     let attitudes = db.load_attitudes(name);
                     if !attitudes.is_empty() {
                         println!("  Attitudes:");