* Update `ForkedChainRef` constructor
why:
Initialisation is based on the canonical head which is always zero
after resuming a stopped `ForkedChainRef` based import.
* Update new-base calculator
why:
There is some ambiguous code which might not do what the comment
implies. In short, an unsigned condition like `2u - 3u < 1u => false`
is coded where the comment suggests that `2 - 3 < 1 => true` is meant.
This patch fixes notorious crashes when resuming import after a stop.
* rename nimbus binary to nimbus_execution_client
* additional replacements
* makefile and dockerfile
* fix ci building errors
* github workflows
* improved Makefile target
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Co-authored-by: Pedro Miranda <pedro.miranda@nimbus.team>