refactor(api): read the remaining settings and admin route bodies through parseJsonBody

Admin, coach, consent, chart-overlay, device registration, insights
feedback and provider chain, ECG ingest, onboarding, search and the AI
provider settings move to parseJsonBody with the same message, error
code, status and wide-event action they answered with. A refusal whose
annotate meta is computed from the issues, or puts its keys in another
order than the helper would, keeps that annotate verbatim in onInvalid.

The routes that still call safeJson do something between the read and the
schema: an optimistic-concurrency token split off the body, a count cap
answered first, a refunded quota slot, a conditional read, a non-Zod
check, or the body handed to a service.

src/app/api/user/ai-provider/route.ts

@@ -1,13 +1,8 @@
 import { NextRequest } from "next/server";
 import { apiHandler, requireAuth } from "@/lib/api-handler";
 import { prisma } from "@/lib/db";
-import {
-  apiSuccess,
-  apiError,
-  getClientIp,
-  returnAllZodIssues,
-  safeJson,
-} from "@/lib/api-response";
+import { apiSuccess, apiError, getClientIp } from "@/lib/api-response";
+import { parseJsonBody } from "@/lib/api/body";
 import { auditLog } from "@/lib/auth/audit";
 import { isPublicUrl } from "@/lib/validations/notifications";
 import { isLocalAiHostAllowed } from "@/lib/ai/local-host-allowlist";
@@ -170,30 +165,26 @@ export const PATCH = apiHandler(async (request: NextRequest) => {
   const { user } = await requireAuth();
   annotate({ action: { name: "user.ai-provider.update" } });
 
-  const { data: rawBody, error } = await safeJson<unknown>(request, {
-    maxBytes: 64 * 1024,
-  });
-  if (error) return error;
-
   // Every accepted field states its type in the schema, so a wrongly-typed
   // value is a named issue rather than a key quietly dropped on the floor.
   // The multi-issue envelope is safe to return even though this body carries
   // plaintext credentials: Zod's type and range messages name the received
   // TYPE, never the received value. See the note in the validations module
   // before adding a `.refine()` here.
-  const parsed = aiProviderPatchSchema.safeParse(rawBody);
-  if (!parsed.success) {
-    annotate({
-      action: { name: "user.ai-provider.update" },
-      meta: {
-        outcome: "validation_failed",
-        issue_count: parsed.error.issues.length,
-      },
-    });
-    return returnAllZodIssues(parsed.error, 422, {
-      errorCode: "ai_provider.invalid",
-    });
-  }
+  const parsed = await parseJsonBody(request, aiProviderPatchSchema, {
+    maxBytes: 64 * 1024,
+    errorCode: "ai_provider.invalid",
+    onInvalid: (error) => {
+      annotate({
+        action: { name: "user.ai-provider.update" },
+        meta: {
+          outcome: "validation_failed",
+          issue_count: error.issues.length,
+        },
+      });
+    },
+  });
+  if (!parsed.ok) return parsed.error;
   const body = parsed.data;
 
   // v1.39.3 — whose configuration this is. Settings saved on an admin account