Cleanup: Migrate from ctxutil to option structs where feasible

[dominikschulz]

The ctxutil package was introduced to clean up the signatures and make it (much) easier to channel through UI specific settings and callbacks to the place where they are needed. However effective this approach is, it's something of an anti-pattern and most APIs use some kind of optional option structs (e.g. func (s* Store) Get(key string, opts *GetOptions)).

This makes is more tedious but also a lot more explicit to channel through settings and callbacks.
We should consider if the added clarity is worth the effort.

[dominikschulz]

Much of what should been done has been addressed by #2395. We can always do more cleanups, but for the sake of this issue I'm happy.