index: Implement block filter index with write operations.

Summary:
This is a partial backport of Core PR14121 : https://github.com/bitcoin/bitcoin/pull/14121/commits/75a76e36199eba228856d59318cb54ca64ca6b57

Depends on D6335 and D6333

Test Plan:

ninja all check-all

Reviewers: #bitcoin_abc, jasonbcox

Reviewed By: #bitcoin_abc, jasonbcox

Subscribers: jasonbcox

Differential Revision: https://reviews.bitcoinabc.org/D6337