[fix] api-action "member/register": output schema

source/api/actions/member_register.ts

@@ -57,7 +57,32 @@ namespace _espe.api
 					]
 				}),
 				"output_schema": () => ({
-					"nullable": true,
+					"nullable": false,
+					"type": "array",
+					"items": {
+						"nullable": false,
+						"type": "object",
+						"properties": {
+							"incident": {
+								"nullable": false,
+								"type": "string"
+							},
+							"details": {
+								"nullable": false,
+								"type": "object",
+								"properties": {},
+								"additionalProperties": {
+									"nullable": true
+								},
+								"required": []
+							},
+						},
+						"additionalProperties": false,
+						"required": [
+							"incident",
+							"details",
+						]
+					}
 				}),
 				"query_parameters": [
 					{