Note Reader improvements

[TomasArrachea]

In #1843, an InputNoteReader was introduced for interating through consumed input notes. It can be extended to also allow iterating through non consumed input notes. Additionally, we can add support for output notes by generalizing to a single NoteReader. More context in #1782.

Separately, there are some simplifications to be done to the existing InputNoteReader, as stated in the #1843 (review)

[AlexWaker]

If no one’s working on this yet, I’d be happy to pick it up. I’m planning to extend the reader into a more general-purpose tool. I took a quick look at the code—right now InputNodeReader is only used in the Rust client and in tests, and hasn’t been used in the Web client yet, so it feels like a pretty low-risk change.

[TomasArrachea]

Separately, there are some simplifications to be done to the existing InputNoteReader, as stated in the #1843 (review)

These have already been addressed by #1925