decouple eth2 from store and lighthouse_network (#6680)

- #6452 (partially)


  Remove dependencies on `store` and `lighthouse_network`  from `eth2`. This was achieved as follows:

- depend on `enr` and `multiaddr` directly instead of using `lighthouse_network`'s reexports.
- make `lighthouse_network` responsible for converting between API and internal types.
- in two cases, remove complex internal types and use the generic `serde_json::Value` instead - this is not ideal, but should be fine for now, as this affects two internal non-spec endpoints which are meant for debugging, unstable, and subject to change without notice anyway. Inspired by #6679. The alternative is to move all relevant types to `eth2` or `types` instead - what do you think?

beacon_node/http_api/src/database.rs

@@ -1,7 +1,17 @@
 use beacon_chain::store::metadata::CURRENT_SCHEMA_VERSION;
 use beacon_chain::{BeaconChain, BeaconChainTypes};
-use eth2::lighthouse::DatabaseInfo;
+use serde::Serialize;
 use std::sync::Arc;
+use store::{AnchorInfo, BlobInfo, Split, StoreConfig};
+
+#[derive(Debug, Serialize)]
+pub struct DatabaseInfo {
+    pub schema_version: u64,
+    pub config: StoreConfig,
+    pub split: Split,
+    pub anchor: AnchorInfo,
+    pub blob_info: BlobInfo,
+}
 
 pub fn info<T: BeaconChainTypes>(
     chain: Arc<BeaconChain<T>>,