create change log for v0.4.1

docs: add v0.4.0 upgrade guide (#220)

* docs: add v0.4.0 upgrade guide

* docs: add Storage V2 section to v0.4.0 upgrade guide

* docs: consolidate upgrade guides into single v0.4.0 migration doc

Split changelog content from migration guide per review feedback.
Move new features and bug fixes to CHANGELOG.md, slim the upgrade
guide to config-only migration steps. Remove v0.3.0 upgrade guide
as v0.4.0 now covers upgrades from all previous versions.

* changlog changes

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Co-authored-by: tac0turtle <marko@baricevic.me>

ev-reth v0.4.0-beta

ev-reth v0.3.0-beta

EV-Reth v0.2.2

EV-Reth v0.2.1

EV-Reth v0.2.0

make the readme more informant for the block mismatch (#57)