Add health-check to Zebra (jsonrpsee based)

[seniakalma]

Motivation

When Zebra runs in different orchestration systems (ECS, K8s), and when oad balancers route traffic to it there's a need for simple HTTP probes to avoid routing traffic to un-healthy nodes, and Zebra has no readiness/liveness HTTP checks to validate this.

Closes ZcashFoundation#8830.

Solution

Use the current JSON RPC (RPSEE) server and add a simple GET health endpoint to it that returns the following details:
curl -s http://127.0.0.1:8232/health
response:
{ "status": "healthy", "version": "1.0.0-beta.41", "git_tag": "v1.0.0-rc.1", "git_commit": "75397cd59d0bac4b4c1e71187bb8af7494efb8b4", "timestamp": "2025-09-02T22:35:14.756599+00:00" }

Tests

A manual test of running the node locally and checking that the endpoint returns the health information correctly for a GET request for /health
In addition to that, those 2 snapshots tests were added:

• Mainnet test (get_health_info_status@mainnet_10.snap)
  Checks that calling get_health_info_status on mainnet returns:
  { "status": "healthy" }

Testnet test (get_health_info_status@testnet_10.snap)
Checks that calling get_health_info_status on testnet also returns:
{ "status": "healthy" }

Follow-up Work

Possible to add or adapt any information returned for that request.

PR Checklist

• The PR name is suitable for the release notes.
• The PR follows the contribution guidelines.
• The library crate changelogs are up to date.
• The solution is tested.
• The documentation is up to date.

[seniakalma]

The previous 10 second wait wasn't enough