First version of OIS models

docs/definitions/models/errors/validation-error.smithy

+$version: "2.0"
+
+namespace c4.digit.ec.europa.eu
+
+@mixin
+structure Error {
+    @required
+    code: Integer
+
+    @required
+    message: String
+}
+
+@error("client")
+structure ValidationError with [Error] {
+}
+
+@error("server")
+structure InternalError with [Error] {
+}