* remove ethers-core

* test

* return ethereum and add a feature

* lint fixes

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Co-authored-by: s1fr0 <28568419+s1fr0@users.noreply.github.com>
Co-authored-by: tyshkor <tyshko1@gmail.com>

* Improve r1cs_reader for Circom 2

Shamelessly taken from https://github.com/poma/zkutil/pull/7/files by @lispc

* Document Seek type restriction

* Doc linter: use automatic links

* Use iter for iterating over sections

* Better error handling with ok_or_else

* Revert "Use iter for iterating over sections"

This reverts commit bc88c72659.