feat: Strassen's matrix multiplication algorithm added

Author: sourav-625

matrix/strassen_matrix_multiplication.py matrix/strassen_matrix_multiply.pymatrix/strassen_matrix_multiplication.py renamed to matrix/strassen_matrix_multiply.py

@@ -129,4 +129,4 @@ def _strassen_recursive(A: Matrix, B: Matrix, threshold: int) -> Matrix:
     # verify against naive
     expected = naive_mul(A, B)
     assert C == expected, "Strassen result differs from naive multiplication!"
-    print("Verified: result matches naive multiplication.")
+    print("Verified: result matches naive multiplication.")