chore(*): add mathlib4 synchronization comments (#19194)
Regenerated from the [port status wiki page](https://github.com/leanprover-community/mathlib/wiki/mathlib4-port-status).
Relates to the following files:
* `algebra.continued_fractions.computation.approximations`
* `analysis.inner_product_space.rayleigh`
* `analysis.inner_product_space.spectrum`
* `analysis.normed.group.SemiNormedGroup`
* `category_theory.closed.functor`
* `field_theory.splitting_field.construction`
* `geometry.euclidean.angle.sphere`
* `linear_algebra.matrix.pos_def`
* `linear_algebra.matrix.spectrum`
* `order.category.BoolAlg`
* `order.category.FinBddDistLat`
* `ring_theory.local_properties`
* `ring_theory.ring_hom.surjective`
* `topology.sheaves.locally_surjective`
Author
github-actions[bot]
