[light-client] Fix light client rpc (#19028)

## Description 

Modernise the RPC used in the light client:
- Use GraphQL to get the end-of-epoch checkpoint.
- Use the supported Rust SDK to get objects and other info.
- Use a generic object store, by default provided by Mysten, for the
full checkpoint data.
- Add a cache to package loader since we observed the same package
downloaded multiple times.

## Test plan 

Existing unit tests, and manual CLI invocations.

crates/sui-light-client/.gitignore

@@ -0,0 +1 @@
+checkpoints_dir/*

crates/sui-light-client/Cargo.toml

@@ -27,8 +27,12 @@ serde_json.workspace = true
 sui-types.workspace = true
 sui-config.workspace = true
 sui-rest-api.workspace = true
-sui-json.workspace = true
 sui-sdk.workspace = true
 move-binary-format.workspace = true
 sui-json-rpc-types.workspace = true
 sui-package-resolver.workspace = true
+url.workspace = true
+reqwest.workspace = true
+object_store.workspace = true
+env_logger = "0.11.5"
+log = "0.4.22"

crates/sui-light-client/example_config/light_client.yaml

@@ -1,3 +1,5 @@
-full_node_url: "http://ord-mnt-rpcbig-06.mainnet.sui.io:9000"
+full_node_url: "https://fullnode.mainnet.sui.io:443"
 checkpoint_summary_dir: "checkpoints_dir"
-genesis_filename: "genesis.blob"
+genesis_filename: "genesis.blob"
+object_store_url: "https://checkpoints.mainnet.sui.io"
+graphql_url: "https://sui-mainnet.mystenlabs.com/graphql"