Misc. dependency cleanup (#6810)

* remove ensure_dir_exists (2 deps saved)

* group UNHANDLED_ERRORs into a generic (2 deps saved)

* Introduce separate `health_metrics` crate

* separate health_metrics crate

* remove metrics from warp_utils

* move ProcessHealth::observe and SystemHealth::observe to health_metrics

* fix errors

* nitpick `Cargo.toml`s

---------

Co-authored-by: Daniel Knopik <daniel@dknopik.de>
# Conflicts:
#	Cargo.toml

validator_client/http_api/Cargo.toml

@@ -21,6 +21,7 @@ eth2_keystore  = { workspace = true }
 ethereum_serde_utils = { workspace = true }
 filesystem = { workspace = true }
 graffiti_file = { workspace = true }
+health_metrics = { workspace = true }
 initialized_validators = { workspace = true }
 lighthouse_version = { workspace = true }
 logging = { workspace = true }

validator_client/http_api/src/lib.rs

@@ -32,6 +32,7 @@ use eth2::lighthouse_vc::{
         PublicKeyBytes, SetGraffitiRequest,
     },
 };
+use health_metrics::observe::Observe;
 use lighthouse_version::version_with_platform;
 use logging::SSELoggingComponents;
 use parking_lot::RwLock;

validator_client/http_metrics/Cargo.toml

@@ -5,6 +5,7 @@ edition = { workspace = true }
 authors = ["Sigma Prime <contact@sigmaprime.io>"]
 
 [dependencies]
+health_metrics = { workspace = true }
 lighthouse_version = { workspace = true }
 malloc_utils = { workspace = true }
 metrics = { workspace = true }

validator_client/http_metrics/src/lib.rs

@@ -206,7 +206,7 @@ pub fn gather_prometheus_metrics<E: EthSpec>(
         scrape_allocator_metrics();
     }
 
-    warp_utils::metrics::scrape_health_metrics();
+    health_metrics::metrics::scrape_health_metrics();
 
     encoder
         .encode(&metrics::gather(), &mut buffer)