uplift: Add 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

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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