Multiple Addresses for Server

# Multiple Addresses for Registrar and Verifier
- One-line enhancement description (can be used as a release note):
Adding the ability to specify multiple addresses for the Registrar, or Registrar and Verifier, to improve availability and security. These would be present in the config and randomly selected from, with re-selection occurring after connection failures.

- Keylime Enhancement Proposal: https://github.com/keylime/enhancements/pull/120
- Primary contact (assignee): @Isaac-Matthews
- Enhancement target (which target equals to which milestone):
- Alpha release target (x.y)
- Beta release target (x.y)
- Stable release target (x.y)

This is an enhancement for the [issue originally submitted in the rust-keylime repo.](https://github.com/keylime/rust-keylime/issues/947#issuecomment-2684914304)
This was discussed in the [meeting on 26/02/25.](https://github.com/keylime/meetings/issues/85)

_Please to keep this description up to date._

Start with Keylime Enhancement Proposal PR #120 and the original rust-keylime issue referenced in this issue. Clarify the configuration format, address selection, and connection-failure reselection behavior; completion should cover the agreed Registrar and Verifier multi-address requirements.

Written by the indexing model from the issue text.