fix: add missing JS files and logic

index.html

@@ -49,7 +49,7 @@
                     <label for="gramAmount">Amount (grams)</label>
                     <input type="number" id="gramAmount" min="1" step="1" value="100">
                 </div>
-                <button class="add-btn" onclick="addFood()">Add Food</button>
+                <button class="add-btn" id="add-food-btn">Add Food</button>
             </div>
             <div id="food-preview" class="add-food-form-item display-none">
               <p>Calories: 0 - Protein: 0 - Fat: 0 - Carbohydrates: 0</p>
@@ -62,6 +62,7 @@
                 <table class="food-table">
                     <thead>
                         <tr>
+                            <th class="hidden-column">ID</th>
                             <th>Time</th>
                             <th>Food</th>
                             <th>Grams</th>
@@ -82,9 +83,9 @@
 
         <div class="calendar-section">
             <div class="calendar-header">
-                <button class="calendar-nav" onclick="previousMonth()">‹</button>
+                <button class="calendar-nav" id="previous-month-btn">‹</button>
                 <div class="calendar-title" id="calendarTitle">Month Year</div>
-                <button class="calendar-nav" onclick="nextMonth()">›</button>
+                <button class="calendar-nav" id="next-month-btn">›</button>
             </div>
             <div class="calendar-grid" id="calendarGrid">
                 <!-- Calendar will be generated here -->
@@ -92,7 +93,6 @@
         </div>
     </div>
 
-    <script src="foodDatabase.js"></script>
-    <script src="index.js"></script>
+    <script type="module" src="index.js"></script>
 </body>
 </html>