chore(*): add mathlib4 synchronization comments (#18272)
Regenerated from the [port status wiki page](https://github.com/leanprover-community/mathlib/wiki/mathlib4-port-status).
Relates to the following files:
* `algebra.big_operators.finprod`
* `algebra.group.unique_prods`
* `algebra.star.pointwise`
* `algebra.tropical.big_operators`
* `combinatorics.hall.finite`
* `combinatorics.pigeonhole`
* `data.countable.basic`
* `data.fin.vec_notation`
* `data.fintype.order`
* `data.typevec`
* `data.vector.zip`
* `data.zmod.defs`
* `logic.equiv.fin`
* `order.filter.basic`
* `order.filter.curry`
* `order.filter.extr`
* `order.filter.prod`
