refactored notificatoin / tgsettle responsibility boundaries

api/proto/common/gateway/v1/gateway.proto

@@ -7,7 +7,8 @@ option go_package = "github.com/tech/sendico/pkg/proto/common/gateway/v1;gateway
 import "api/proto/common/money/v1/money.proto";
 import "api/proto/payments/endpoint/v1/endpoint.proto";
 
-
+// Operation enumerates gateway-level operations that can be performed on a
+// payment method.
 enum Operation {
   OPERATION_UNSPECIFIED     = 0;
   OPERATION_AUTHORIZE       = 1;
@@ -126,6 +127,7 @@ message RailCapabilities {
   bool can_release = 7;
 }
 
+// LimitsOverride provides per-currency overrides for global limit settings.
 message LimitsOverride {
   string max_volume = 1;
   string min_amount = 2;
@@ -166,6 +168,7 @@ enum OperationResult {
   OPERATION_RESULT_CANCELLED   = 3;
 }
 
+// OperationError describes a failure returned by a gateway operation.
 message OperationError {
   string code            = 1;
   string message         = 2;
@@ -173,6 +176,8 @@ message OperationError {
   bool should_rollback  = 4;
 }
 
+// OperationExecutionStatus reports the result of executing a single gateway
+// operation, including the settled amount and any error.
 message OperationExecutionStatus {
   string idempotency_key = 1;
   string operation_ref   = 2;