Improve TestNet with Full Node Simulation

[Luka-Loncar]

Problem Statement

Currently, our test environment doesn't accurately simulate production conditions because the test net metagraph isn't sufficiently populated. This prevents us from catching certain issues that only manifest with a full metagraph (e.g., recent registration/deregistration race conditions in subnet 59).

Proposed Solution
Create a system to simulate a full metagraph in the test environment by:

• Running multiple validator instances in Docker containers on a single machine
• Automating the registration process for these test nodes
• Maintaining a sufficient number of active nodes to replicate production conditions