Fix #51245 vertex tool topo crs mismatch

[Djedouas]

Description

Fixes #51245 where topological editing with vertex tool does not work when layer CRS and project CRS are different.

I fully tested in the GUI, but I can't manage to make the test work... I must miss something when changing the map CRS with the API...

The first commit is the fix.
The second commit is my WIP with the test, if someone could take a look at it, it would be great!

Thanks.