This pull request introduces a queue for legacy sidecar conversion to
handle transactions that persist after the Osaka fork. Simply dropping
these transactions would significantly harm the user experience.
To balance usability with system complexity, we have introduced a
conversion time window of two hours post Osaka fork. During this period,
the system will accept legacy blob transactions and convert them in a
background process.
After the window, all legacy transactions will be rejected. Notably, all
the blob transactions will be validated statically before the conversion,
and also all conversion are performed in a single thread, minimize the risk
of being DoS.
We believe this two hour window provides sufficient time to process
in-flight legacy transactions and allows submitters to migrate to the
new format.
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Co-authored-by: Felix Lange <fjl@twurst.com>
