uplift gossip package from evm repositories

[JonathanOppenheimer]

Why this should be merged

There are packages in subnet-evm and coreth that share a lot of functionality / are mirrored. These packages should be uplifted to AvalancheGo to prevent the duplicative maintenance of two sets of the same code. I recently was syncing changes between coreth and subnet-evm for these gossip changes, and it would be better if this code was just in AvalancheGo

Here are the packages being unified and uplifted:
coreth: https://github.com/ava-labs/coreth/tree/master/plugin/evm/gossip
subnet-evm: https://github.com/ava-labs/subnet-evm/tree/master/plugin/evm/gossip

How this was tested

This is currently 'dead' code; after a new AvalancheGo release is dropped, we can use the code in the evm repositories.

Need to be documented in RELEASES.md?

No

[Copilot]

Pull Request Overview

This PR uplifts the gossip package from EVM repositories (subnet-evm and coreth) to AvalancheGo to reduce code duplication and maintenance overhead. The change introduces a new transaction gossip handler that combines push and pull gossip functionality with throttling and validator filtering.

Key changes:

• Adds a new gossip package under vms/evm/ containing a transaction gossip handler
• Implements a composite handler that wraps both app gossip and app request handlers with different access controls

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[ARR4N]

Is this the "temporary" directory, or is it the final destination for this code? If the latter, I'll provide more thorough comments on style.

[JonathanOppenheimer]

Is this the "temporary" directory, or is it the final destination for this code? If the latter, I'll provide more thorough comments on style.

This is the final destination for the code. 'uplifting' is the is the process of cleaning up, aligning with AvalancheGo standards, etc. so these typically get more thorough reviews.