LibGfx: Add Matrix::operator*(T scalar)

Author: https://github.com/MacDue
Commit: https://github.com/SerenityOS/serenity/commit/3d532571bb
Pull-request: https://github.com/SerenityOS/serenity/pull/15430
Reviewed-by: https://github.com/LucasChollet

Userland/Libraries/LibGfx/Matrix.h

@@ -104,6 +104,21 @@ public:
         return division;
     }
 
+    friend constexpr Matrix operator*(Matrix const& matrix, T scalar)
+    {
+        Matrix scaled;
+        for (size_t i = 0; i < N; ++i) {
+            for (size_t j = 0; j < N; ++j)
+                scaled.m_elements[i][j] = matrix.m_elements[i][j] * scalar;
+        }
+        return scaled;
+    }
+
+    friend constexpr Matrix operator*(T scalar, Matrix const& matrix)
+    {
+        return matrix * scalar;
+    }
+
     [[nodiscard]] constexpr Matrix adjugate() const
     {
         if constexpr (N == 1)