chg: dev: massive refactor on front-end - and remove unnecessary deps #4

src/Util/TopicManager.php

@@ -352,9 +352,10 @@ class TopicManager implements TopicManagerInterface
     private function getLeftMines(array $grid, array $alreadyRevealed): array
     {
         $mines = [];
+
         foreach ($grid as $r => $row) {
             foreach ($row as $c => $value) {
-                if ('m' === $value && !isset($alreadyRevealed[$r . ',' . $c])) {
+                if ('m' === $value && !isset($alreadyRevealed["$r,$c"])) {
                     $mines[] = ['row' => $r, 'col' => $c];
                 }
             }