feat : Modal pour commentaires

lib/ui/common/post_card_widget.dart

@@ -230,11 +230,36 @@ class _PostCardWidgetState extends State<PostCardWidget> {
   void showCommentSheet() {
     showModalBottomSheet(
       context: context,
+      isScrollControlled: true,
       builder: (context) {
-        return Container(
-          height: 1000,
+        return FractionallySizedBox(
+          heightFactor: 0.9,
+          child: Container(
+            padding: const EdgeInsets.all(16.0),
+            child: Column(
+              children: [
+                Container(
+                  width: 40,
+                  height: 4,
+                  margin: const EdgeInsets.only(bottom: 16.0),
+                  decoration: BoxDecoration(
+                    color: Colors.grey[300],
+                    borderRadius: BorderRadius.circular(2),
+                  ),
+                ),
+                Expanded(
                   child: Center(
-            child: Text('Section des commentaires'),
+                    child: Text(
+                      'Section des commentaires (à implémenter)',
+                      style: Theme.of(context).textTheme.headlineMedium?.copyWith(
+                        color: Colors.grey[600],
+                      ),
+                      textAlign: TextAlign.center,
+                    ),
+                  ),
+                ),
+              ],
+            ),
           ),
         );
       },