Allow `eth_call` and `eth_estimateGas` from contract and non-existent senders

[LesnyRumcajs]

Summary

Basically port filecoin-project/lotus#13724

Make sure to review that PR carefully and implement the changes into idiomatic Rust (🌲 edition) code, not just translate to Golang, especially potentially slow bits (we have a couple of exclusive tools in our arsenal)

Completion Criteria

• Port the implementation of fix(eth): allow eth_call and eth_estimateGas from contract and non-existent senders filecoin-project/lotus#13724 to Forest (including tests)
• Benchmark the changes against Lotus - they must be at least as performant out of the box.

Additional Links & Resources

[0xDevNinja]

I would like to take this. Plan is to mirror the two cases from the Lotus PR: for a non existent sender, apply an implicit zero value send first so an ephemeral placeholder actor exists, then run the call; for a contract sender, run through the FVM implicit path so the account type, nonce and balance checks are skipped. Forest already routes these calls through apply_implicit_message, so I will confirm how much of the contract sender case already works, add the missing placeholder creation, and port the tests including the estimate parity and round trip checks. Will benchmark against Lotus before marking it ready.

[0xDevNinja]

Got it, my mistake. Happy to raise this again once it's assigned. Work's ready on my side whenever you give the go ahead.

[sudo-shashank]

Thanks, @0xDevNinja. I’ve picked up this issue. Please feel free to explore other open issues.