Fix check looped snake

fastlane/metadata/android/en-US/changelogs/24.txt

+Fix collision detection.

fastlane/metadata/android/fr-FR/changelogs/24.txt

+Correction sur détection de collision.

lib/models/activity/activity.dart

+import 'dart:math';
+
 import 'package:flutter_custom_toolbox/flutter_toolbox.dart';
 
 import 'package:snake/models/activity/board.dart';
@@ -158,8 +160,11 @@ class Activity {
       return false;
     }
 
+    // first snake cell to check (end of tail), after next move
+    final int start = max(1, snake.cells.length - snake.size);
+
     // check head is not looped on snake body
-    for (int i = 0; i < snake.cells.length - 1; i++) {
+    for (int i = start; i < snake.cells.length - 1; i++) {
       if (head.col == snake.cells[i].col && head.row == snake.cells[i].row) {
         return false;
       }

pubspec.yaml

@@ -3,7 +3,7 @@ description: snake game
 
 publish_to: "none"
 
-version: 0.5.3+23
+version: 0.5.4+24
 
 environment:
   sdk: "^3.0.0"