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/combat.rs

@@ -45,8 +45,8 @@ pub fn resolve_combat_tick(
 
     let npc_hp_before = instance.hp;
     let conn = state.players.get(&player_id)?;
-    let p_atk = conn.player.effective_attack();
-    let p_def = conn.player.effective_defense();
+    let p_atk = conn.player.effective_attack(&state.world);
+    let p_def = conn.player.effective_defense(&state.world);
     let _ = conn;
 
     let mut out = String::new();