refactor: Remove ES6 module syntax and reorder script loading

ai.js

@@ -6,8 +6,7 @@ const ANIMAL_HUNGER_MAX = 100;
 /**********************************************************************
  * CITIZEN AI
  **********************************************************************/
-// Export functions
-export function updateCitizen(cit) {
+function updateCitizen(cit) {
   cit.hunger += HUNGER_INCREMENT;
   if(cit.hunger > HUNGER_MAX) cit.hunger = HUNGER_MAX;
 
@@ -54,7 +53,7 @@ export function updateCitizen(cit) {
 /**********************************************************************
  * ANIMAL AI
  **********************************************************************/
-export function updateAnimal(ani) {
+function updateAnimal(ani) {
   if(ani.type === "Rabbit") {
     updateRabbit(ani);
   }

game.js

@@ -1,8 +1,7 @@
 /**********************************************************************
  * GAME CORE
  **********************************************************************/
-// Import AI functions
-import { updateCitizen, updateAnimal } from './ai.js';
+// AI functions are defined in ai.js and loaded via script tag
 let frameCount = 0;
 let money = 5000;  // Start with 5000
 let purchaseMode = null;

index.html

@@ -207,12 +207,12 @@
   <div id="log"></div>
 </div>
 
-<script src="game.js"></script>
 <script src="entities.js"></script>
 <script src="utils.js"></script>
 <script src="ai.js"></script>
 <script src="render.js"></script>
 <script src="events.js"></script>
+<script src="game.js"></script>
 
 <script>
 /**********************************************************************