The matrix \(\mathbf{M}\) is defined by
\(\mathbf{M}=\left(\begin{array}{ccc}
2 & m & 1 \\
0 & m & 7 \\
0 & 0 & 1
\end{array}\right),\)
where \(m \neq 0,1,2\).
(i) Find a matrix \(\mathbf{P}\) and a diagonal matrix \(\mathbf{D}\) such that \(\mathbf{M}=\mathbf{P D P}^{-1}\).

(ii) Find \(\mathbf{M}^{7} \mathbf{P}\).