added missing != operator for vector2 (required by gcc on turring)

src/engine/vector2.hpp

@@ -57,6 +57,7 @@ public:
     Vector2& operator%=(const T& other) { pos_x %= other; pos_y %= other; return *this; }
 
     bool operator==(const Vector2& other) const { return pos_x == other.pos_x && pos_y == other.pos_y; }
+    bool operator!=(const Vector2& other) const { return pos_x != other.pos_x || pos_y != other.pos_y; }
 
     // Utilities
     [[nodiscard]] T       length() const { return static_cast<T>(std::sqrt(static_cast<double>(pos_x * pos_x + pos_y * pos_y))); }