chore(api): keep one onboarding entry in the error-code catalogue

Two branches each added an onboarding surface to the catalogue; the object literal carried the key twice and the second entry hid the first from the guard.

src/lib/openapi/error-codes.ts

@@ -234,8 +234,12 @@ export const ERROR_CODE_CATALOGUE: Readonly<Record<string, readonly string[]>> =
       "nutrient.water.invalid_day",
     ],
     onboarding: [
+      "onboarding.answers.invalid",
+      "onboarding.answers.rateLimited",
       "onboarding.complete.invalid",
       "onboarding.disclaimer.invalid",
+      "onboarding.restart.invalid",
+      "onboarding.restart.rateLimited",
       "onboarding.step.completed",
       "onboarding.step.concurrent",
       "onboarding.step.invalid",
@@ -244,12 +248,6 @@ export const ERROR_CODE_CATALOGUE: Readonly<Record<string, readonly string[]>> =
       "onboarding.tour.invalid",
       "onboarding.user.notFound",
     ],
-    onboarding: [
-      "onboarding.answers.invalid",
-      "onboarding.answers.rateLimited",
-      "onboarding.restart.invalid",
-      "onboarding.restart.rateLimited",
-    ],
     personal_records: ["personal_records.invalid_query"],
     practitioner: ["practitioner.invalid"],
     profile: [