Make sure scanner database is accessed using the correct types

[teor2345]

Motivation

During the scanner MVP, it was easy to change the column family's types, but forget to update the code everywhere. There were at least two bugs like this, from two different developers.

Instead, we can make each column family strongly typed, so it can only be accessed using the correct types.

Preparation for #7833, let's document the easier way this PR implements.

PR Author Checklist

Check before marking the PR as ready for review:

• Will the PR name make sense to users?
• Does the PR have a priority label?
• Have you added or updated tests?
• Is the documentation up to date?

If a checkbox isn't relevant to the PR, mark it as done.

API & Rust Reference

https://docs.rs/rocksdb/latest/rocksdb/struct.WriteBatchWithTransaction.html

https://doc.rust-lang.org/book/ch10-03-lifetime-syntax.html
https://doc.rust-lang.org/std/marker/struct.PhantomData.html

Complex Code or Requirements

Solution

Production:

• Define types for reading and writing sapling transaction ID results
• Simplify implementations using typed column families
• Make sure each method writes its own batch
• Implement common methods as a trivial trait

Docs & debugging:

• impl Debug and PartialEq on some database types to improve debugging
• Update docs & parameter names
• Deprecate some traits that we shouldn't use for new column families

Unrelated cleanups:

• impl TryFrom<zcash_primitives::BlockHeight> for Height
• Simplify logging macros in the scanner

We can't make the column family name string constant part of the type, because Rust doesn't support String const generics yet.

Testing

This PR is well covered by existing tests, which pass.

Review

This is a routine cleanup/internal enhancement.

Reviewer Checklist

Check before approving the PR:

• Does the PR scope match the ticket?
• Are there enough tests to make sure it works? Do the tests cover the PR motivation?
• Are all the PR blockers dealt with?
  PR blockers can be dealt with in new tickets or PRs.

And check the PR Author checklist is complete.

Follow Up Work

Use the new TypedColumnFamily and WriteTypedBatch for existing state column families. We might discover some bugs this way.

Document how to set up a new column family using these types - #7833

[upbqdn]

utACK.

Looks great!