fix: health endpoint now detects stopped block production (#2800)

This commit fixes issue #2643 where the health endpoint still reports OK
when a node has stopped producing blocks.

Closes #2643

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## Overview

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Needs merge and tag of tastora PR
celestiaorg/tastora#149

---------

Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com>

Author: randygrok

CHANGELOG.md

@@ -9,10 +9,18 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
+### Added
+
+- Enhanced health check system with separate liveness (`/health/live`) and readiness (`/health/ready`) HTTP endpoints. Readiness endpoint includes P2P listening check and aggregator block production rate validation (5x block time threshold). ([#2800](https://github.com/evstack/ev-node/pull/2800))
+
 ### Changed
 
 - Use cache instead of in memory store for reaper. Persist cache on reload. Autoclean after 24 hours. ([#2811](https://github.com/evstack/ev-node/pull/2811))
 
+### Removed
+
+- **BREAKING:** Removed `evnode.v1.HealthService` gRPC endpoint. Use HTTP endpoints: `GET /health/live` and `GET /health/ready`. ([#2800](https://github.com/evstack/ev-node/pull/2800))
+
 ## v1.0.0-beta.9
 
 ### Added