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/components/security-schemes.json

@@ -0,0 +1,6 @@
+{
+	"BearerAuth": {
+		"type": "http",
+		"scheme": "bearer"
+	}
+}