refactor: enforce enum machine codes #18

Use owner enums for known codes; preserve wire values and unknown fallbacks.

Verified npm ci and verify: 379 tests, 5 lint checks, app and Storybook builds.

src/shared/api/client.ts

@@ -3,7 +3,7 @@ import createQueryClient from "openapi-react-query";
 
 import type { paths } from "./generated/schema";
 
-import { apiErrorCode } from "./problem-details";
+import { ApiErrorCode, apiErrorCode, isApiErrorCode } from "./problem-details";
 
 const HTTP_UNAUTHORIZED = 401;
 
@@ -101,7 +101,7 @@ async function fetchCurrent(
 	catch {
 		return response;
 	}
-	if (apiErrorCode(problem) !== "UNAUTHORIZED") return response;
+	if (!isApiErrorCode(apiErrorCode(problem), ApiErrorCode.Unauthorized)) return response;
 	if (!isCurrent()) throw new DOMException("Session changed", "AbortError");
 	if (!(await sessionState.handlers.refresh())) {
 		if (isCurrent()) sessionState.handlers.clear();