refactor: wire presim through flashpool

[akundaz]

📝 Summary

Refactor the presim startup so that it starts with the pool. Also hook into the add_transaction function to rework the presim lifecycle. Previously, txs would be added to the pool and the background presim task would remove them if the tx reverted, now we run the presim task and then add it to the pool if it succeeds. This is now possible because we access the transaction validator from the inner pool and use it to run the several quick checks first.

💡 Motivation and Context

Presim should be managed closer to the pool.

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✅ I have completed the following steps:

• Run make lint
• Run make test
• Added tests (if applicable)

[avalonche]

tokio::task::spawn_blocking() in pool/presim.rs uses Tokio's shared blocking pool which is used by the block building pipeline and can starve resources for block building - consider bounding the number of concurrent presim processes or have its own dedicated threads in a different pool

[akundaz]

tokio::task::spawn_blocking() in pool/presim.rs uses Tokio's shared blocking pool which is used by the block building pipeline and can starve resources for block building - consider bounding the number of concurrent presim processes or have its own dedicated threads in a different pool

this is a bit involved, will definitely do in a follow up