Sections 14 and 241 were not totally invalidated. They were invalidated to the extent that they relate to physician-assisted dying. So, we can quite easily add a paragraph. I am giving you the simplest answer, but the analysis could be refined.
If you were in a hurry and simply wanted to align yourselves on the Supreme Court decision and the Charter, you could enact similar exceptions to sections 14 and 241. I have not done any final drafting exercises yet, but you could say that those provisions do not apply to a competent adult who asks for physician-assisted dying and whose state meets the conditions set out by the Supreme Court.
That would be the easiest common denominator to achieve something in the very short term. That exception could then be refined, among other things, to have it apply on condition that the physician's action be compatible with the provincial act or what have you. You can always add other elements to it. That is what you need to do if you want to deal with the most pressing matters and take your time to debate things afterwards. At this stage, you may want to avoid biting off more than you can chew, as the French proverb says.
In minimal terms, you could do that. You could also add regulations regarding access to assisted dying. For instance, should you limit that assistance to Canadian citizens in order to avoid “euthanasia tourism”? Are there other rules you can think of? Basically, you can at this time set limits.