Refactor engine code

.vscode/settings.json

@@ -63,6 +63,20 @@
         "streambuf": "cpp",
         "cinttypes": "cpp",
         "typeinfo": "cpp",
-        "variant": "cpp"
+        "variant": "cpp",
+        "csignal": "cpp",
+        "strstream": "cpp",
+        "bitset": "cpp",
+        "condition_variable": "cpp",
+        "unordered_set": "cpp",
+        "expected": "cpp",
+        "mutex": "cpp",
+        "ranges": "cpp",
+        "semaphore": "cpp",
+        "shared_mutex": "cpp",
+        "stop_token": "cpp",
+        "thread": "cpp",
+        "typeindex": "cpp",
+        "valarray": "cpp"
     }
 }