* [erigon2] Introduce inverted index type
* More inverted index code
* More tests for inverted index
* Think about public and non-public APIs
* Minimise DB access when accessing history
* Work on iterator
* Implementation of inverted iterator
* Test for inverted index
* Assert end of iterators
* Merge of inverted index files and test
* Fix lint
Co-authored-by: Alexey Sharp <alexeysharp@Alexeys-iMac.local>
Co-authored-by: Alex Sharp <alexsharp@Alexs-MacBook-Pro.local>
