wallet: add GetInfo endpoint

Author: torkelrogstad

proto/cusf/mainchain/v1/wallet.proto

@@ -52,6 +52,8 @@ service WalletService {
     returns (ListTransactionsResponse);
   rpc ListUnspentOutputs(ListUnspentOutputsRequest)
     returns (ListUnspentOutputsResponse);
+  rpc GetInfo(GetInfoRequest) 
+    returns (GetInfoResponse);
   rpc SendTransaction(SendTransactionRequest)
     returns (SendTransactionResponse);
   rpc UnlockWallet(UnlockWalletRequest)
@@ -61,6 +63,22 @@ service WalletService {
     returns (stream GenerateBlocksResponse);
 }
 
+message GetInfoRequest {
+}
+
+message GetInfoResponse {
+  // The network the wallet is on
+  string network = 1;
+
+  // Total number of transactions in the wallet
+  uint32 transaction_count = 2;
+
+  // Number of UTXOs in the wallet.
+  uint32 unspent_output_count = 3;
+
+  map<string, string> descriptors = 4;
+}
+
 message BroadcastWithdrawalBundleRequest {
   google.protobuf.UInt32Value sidechain_id = 1;
   google.protobuf.BytesValue transaction = 2;