[ew] Opening /canvas for ew enabled pages

[sharanyavinod]

For certain scenarios, for eg from within apps https://da.live/apps/traverse, it still opens /edit even if ew is enabled for the same page and redirects as expected from browse.

[shsteimer]

Relates to adobe/da-nx#634 (I hadn't opened an issue yet and PR is still in draft cus I haven't yet had time to finish it. a more wholistic solution seems better though. I have no affection for that PR, if someone wants to handle this and close my PR before I get time to finish that is fine with me).