fix(server): restore online client approval UX with sdk management

protobufs/user_agent.proto

@@ -106,6 +106,16 @@ enum VaultState {
   VAULT_STATE_ERROR = 4;
 }
 
+message ClientConnectionRequest {
+  bytes pubkey = 1;
+}
+
+message ClientConnectionResponse {
+  bool approved = 1;
+}
+
+message ClientConnectionCancel {}
+
 message UserAgentRequest {
   oneof payload {
     AuthChallengeRequest auth_challenge_request = 1;
@@ -118,7 +128,7 @@ message UserAgentRequest {
     arbiter.evm.EvmGrantCreateRequest evm_grant_create = 8;
     arbiter.evm.EvmGrantDeleteRequest evm_grant_delete = 9;
     arbiter.evm.EvmGrantListRequest evm_grant_list = 10;
-    // field 11 reserved: was client_connection_response (online approval removed)
+    ClientConnectionResponse client_connection_response = 11;
     SdkClientApproveRequest sdk_client_approve = 12;
     SdkClientRevokeRequest sdk_client_revoke = 13;
     google.protobuf.Empty sdk_client_list = 14;
@@ -136,7 +146,8 @@ message UserAgentResponse {
     arbiter.evm.EvmGrantCreateResponse evm_grant_create = 8;
     arbiter.evm.EvmGrantDeleteResponse evm_grant_delete = 9;
     arbiter.evm.EvmGrantListResponse evm_grant_list = 10;
-    // fields 11, 12 reserved: were client_connection_request, client_connection_cancel (online approval removed)
+    ClientConnectionRequest client_connection_request = 11;
+    ClientConnectionCancel client_connection_cancel = 12;
     SdkClientApproveResponse sdk_client_approve = 13;
     SdkClientRevokeResponse sdk_client_revoke = 14;
     SdkClientListResponse sdk_client_list = 15;