indexes, refactor: Pass Chain interface instead of CChainState class to indexes

Summary:
Passing abstract Chain interface will let indexes run in separate
processes.

This commit does not change behavior in any way.

This is a partial backport of core#25494
https://github.com/bitcoin/bitcoin/pull/25494/commits/33b4d48cfcdf145f49cb2283ac3e2936a4e23fff
Depends on D17704

Test Plan: ninja all check-all

Reviewers: #bitcoin_abc, Fabien

Reviewed By: #bitcoin_abc, Fabien

Subscribers: Fabien

Differential Revision: https://reviews.bitcoinabc.org/D17705