Health issues are certainly within provincial jurisdiction, and provinces have the jurisdiction to legislate to protect the health of their citizens. Canada, federally, has the authority to protect the health of its citizens when people try to cross the international border.
There is a role for provincial governments and legislatures to regulate in that area, but subject to the same considerations, it is exceptional. It does affect civil rights. It should be science based and time limited.
All federal or provincial governments should have in mind that if these proofs of vaccinations are required given the exceptional times that we're in, then in addition to being time limited, let's narrow the scope of these exceptional measures as much as possible, because there is a risk that what is accepted as possible under normal circumstances will become normal afterwards. It is a concern.