Store configuration settings which can modify Storefront should be propagated to Storefront

AC:

• Create a new event which will send a message with Configuration data to Message Broker from Export API
  • collected configuration paths should be described in di.xml
  • only send a message if the value was changed
  • the initial command should collect and send all described configuration data
• Consumers(s) on the Message Broker side save the configuration to the corresponding Service via gRPC
  • configuration in di.xml can be used to determine what configuration should be imported to specified service

Proposed service & message structure:

service Catalog { # will be similar for any service 
  rpc importConfig (ImportConfigRequest) returns (ImportConfigResponse)  {}
}

message ImportConfigRequest {
  repeated Config config = 1;
}

message ImportConfigResponse {
  bool status = 1;
  string message = 2;
}

message Config {
  string name = 1;
  string value = 2;
}