[Chronik] Add fallible Hashed methods for parsing byte slices and hex string

Summary:
Parsing hashes from byte slices and hex strings is fallible, add methods that parse them with proper error handling.

Errors are provided through thiserror, which builds us an error enum with Display implementations.

Test Plan: ninja check-bitcoinsuite

Reviewers: Fabien, #bitcoin_abc

Reviewed By: Fabien, #bitcoin_abc

Differential Revision: https://reviews.bitcoinabc.org/D11715