Refactor API Schema and validation

- /schema now returns full openapi/swagger schema
- That schema is used to validate incoming requests
- And used as a contract in future integration tests
- Moved route files up one level
- Fixed incorrect 404 reponses when getting objects
- Fixed saving new objects and passing jsonschemavalidation

backend/schema/paths/settings/get.json

@@ -0,0 +1,35 @@
+{
+	"operationId": "getSettings",
+	"summary": "Get all settings",
+	"tags": ["Settings"],
+	"security": [
+		{
+			"BearerAuth": ["settings"]
+		}
+	],
+	"responses": {
+		"200": {
+			"description": "200 response",
+			"content": {
+				"application/json": {
+					"examples": {
+						"default": {
+							"value": [
+								{
+									"id": "default-site",
+									"name": "Default Site",
+									"description": "What to show when Nginx is hit with an unknown Host",
+									"value": "congratulations",
+									"meta": {}
+								}
+							]
+						}
+					},
+					"schema": {
+						"$ref": "../../components/setting-list.json"
+					}
+				}
+			}
+		}
+	}
+}