Only spawn_blocking for tx creation in DA queue

[yaziciahmet]

Description

It doesn't make much sense to spawn the whole DA queue in a spawn_blocking, due to the fact that it waits empty for messages most of the time, hence, it doesn't need a whole thread to itself. Instead, with this PR, queue is spawned as a tokio runtime worker, so it doesn't occupy any resources while waiting, but only acquires a thread with spawn_blocking when it's time to create the transaction and find the right prefix (or nonce).

Linked Issues

• Fixes # (issue, if applicable)
• Related to # (issue)

Testing

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Docs

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[codecov]

Codecov Report

Attention: Patch coverage is 71.92982% with 16 lines in your changes missing coverage. Please review.

Project coverage is 77.5%. Comparing base (341f241) to head (804333c).
Report is 1 commits behind head on nightly.

Files with missing lines	Patch %	Lines
...c/helpers/builders/light_client_proof_namespace.rs	55.5%	12 Missing ⚠️
crates/bitcoin-da/src/service.rs	66.6%	4 Missing ⚠️

Additional details and impacted files

Files with missing lines	Coverage Δ
...n-da/src/helpers/builders/batch_proof_namespace.rs	100.0% <100.0%> (ø)
crates/bitcoin-da/src/helpers/builders/tests.rs	100.0% <100.0%> (+1.9%)	⬆️
crates/bitcoin-da/src/service.rs	51.4% <66.6%> (-0.4%)	⬇️
...c/helpers/builders/light_client_proof_namespace.rs	26.9% <55.5%> (+21.4%)	⬆️

[rakanalh]

👍