Storage chains: indexing, renewals and reference counting (#8265)

* Transaction indexing

* Tests and fixes

* Fixed a comment

* Style

* Build

* Style

* Apply suggestions from code review

Co-authored-by: cheme <[email protected]>

* Code review suggestions

* Add missing impl

* Apply suggestions from code review

Co-authored-by: Bastian Köcher <[email protected]>

* impl JoinInput

* Don't store empty slices

* JoinInput operates on slices

Co-authored-by: cheme <[email protected]>
Co-authored-by: Bastian Köcher <[email protected]>