[SRE] Enable VM 2.0 in DevNet for development & testing

Joe suggests:

- DevNet is alive with old Mainnet data (~3M blocks).
- Can enable VM 2.0 via config flag.
- Proposal to transform DevNet into a nightly test network.
- Automated test suite would validate upgrades across Node, Sidecar, and Client.
- DevNet should not be considered production-stable; resets possible after failures.
- Joe is working on scripting architecture to automate refreshes and test execution.

Michał prefers launching DevNet with a fresh state post Mainnet release of 2.0.

No files or tests are named. Start by locating the DevNet configuration flag for VM 2.0, then review the proposed scripting architecture and how Node, Sidecar, and Client tests are run. Done means a repeatable nightly DevNet workflow exists, including refreshes, upgrade validation, and documented reset behavior.

Written by the indexing model from the issue text.