feat(tvix/store): add grpc healthcheck service to daemon

Change-Id: Ib95fc9352a45d54f9a16c8841c7e8f7cbeeaee8c
Reviewed-on: https://cl.tvl.fyi/c/depot/+/12019
Tested-by: BuildkiteCI
Reviewed-by: flokli <flokli@flokli.de>
Autosubmit: yuka <yuka@yuka.dev>

tvix/store/src/bin/tvix-store.rs

@@ -178,8 +178,11 @@ async fn run_cli(cli: Cli) -> Result<(), Box<dyn std::error::Error + Send + Sync
                     .map_request(tvix_tracing::propagate::tonic::accept_trace),
             );
 
+            let (_health_reporter, health_service) = tonic_health::server::health_reporter();
+
             #[allow(unused_mut)]
             let mut router = server
+                .add_service(health_service)
                 .add_service(BlobServiceServer::new(GRPCBlobServiceWrapper::new(
                     blob_service,
                 )))