fix: guard managed setting label inventories

- Treat inherited property names as unavailable settings

- Preserve legacy tile aliases only for declared entries

src/components/settings/__tests__/managed-record-settings-section.test.tsx

@@ -125,4 +125,28 @@ describe("managed record settings forms", () => {
       expect(insights).not.toContain("settings.sharedRecord");
     }
   });
+
+  it.each(["toString", "constructor", "__proto__"])(
+    "renders the unavailable label for prototype property %s",
+    (id) => {
+      const coach = render("coach", {
+        preferences: {
+          excludeMetrics: [id],
+          dataClusters: [id],
+        },
+      });
+      const insights = render("insights", {
+        layout: {
+          version: 2,
+          sections: [{ id, visible: true, order: 0 }],
+          tiles: [{ id, visible: true, order: 0 }],
+        },
+      });
+
+      expect(coach).not.toContain(`>${id}<`);
+      expect(insights).toContain("Unavailable insight");
+      expect(insights).not.toContain(`>${id}<`);
+      expect(insights).not.toContain("settings.sharedRecord");
+    },
+  );
 });

src/components/settings/managed-record-settings-section.tsx

@@ -171,18 +171,30 @@ function formNumber(form: FormData, name: string, fallback: number): number {
   return Number.isFinite(value) ? value : fallback;
 }
 
+function ownStringValue(inventory: object, id: string): string | undefined {
+  if (!Object.hasOwn(inventory, id)) return undefined;
+  const value = Reflect.get(inventory, id);
+  return typeof value === "string" ? value : undefined;
+}
+
 function coachMetricLabel(
   t: ReturnType<typeof useTranslations>["t"],
   metric: (typeof COACH_EXCLUDE_METRICS)[number],
 ): string {
-  return t(COACH_EXCLUDE_METRIC_LABEL_KEYS[metric]);
+  const labelKey = ownStringValue(COACH_EXCLUDE_METRIC_LABEL_KEYS, metric);
+  return labelKey
+    ? t(labelKey)
+    : t("settings.sharedRecord.managedSettings.insights.unknownItem");
 }
 
 function coachClusterLabel(
   t: ReturnType<typeof useTranslations>["t"],
   cluster: (typeof COACH_DATA_CLUSTERS)[number],
 ): string {
-  return t(COACH_DATA_CLUSTER_LABEL_KEYS[cluster]);
+  const labelKey = ownStringValue(COACH_DATA_CLUSTER_LABEL_KEYS, cluster);
+  return labelKey
+    ? t(labelKey)
+    : t("settings.sharedRecord.managedSettings.insights.unknownItem");
 }
 
 function insightItemLabel(
@@ -191,7 +203,7 @@ function insightItemLabel(
   id: string,
 ): string {
   if (kind === "section") {
-    const labelKey = INSIGHTS_SECTION_LABEL_KEYS[id as InsightsSectionId];
+    const labelKey = ownStringValue(INSIGHTS_SECTION_LABEL_KEYS, id);
     return labelKey
       ? t(labelKey)
       : t("settings.sharedRecord.managedSettings.insights.unknownItem");
@@ -199,9 +211,14 @@ function insightItemLabel(
 
   const normalizedId = normalizeInsightsTileId(id);
   if (normalizedId === "overview") return t("insights.navOverview");
-  const tab = SUB_PAGE_TABS[normalizedId as keyof typeof SUB_PAGE_TABS];
-  return tab
-    ? t(tab.labelKey)
+  if (!Object.hasOwn(SUB_PAGE_TABS, normalizedId)) {
+    return t("settings.sharedRecord.managedSettings.insights.unknownItem");
+  }
+
+  const labelKey =
+    SUB_PAGE_TABS[normalizedId as keyof typeof SUB_PAGE_TABS]?.labelKey;
+  return typeof labelKey === "string"
+    ? t(labelKey)
     : t("settings.sharedRecord.managedSettings.insights.unknownItem");
 }
 

src/lib/__tests__/insights-layout.test.ts

@@ -16,9 +16,20 @@ import {
   resolveInsightsLayout,
   serializeInsightsLayout,
   orderedVisibleSectionIds,
+  normalizeInsightsTileId,
   resolveTileLayout,
 } from "@/lib/insights-layout";
 
+describe("normalizeInsightsTileId", () => {
+  it("only resolves own legacy aliases", () => {
+    expect(normalizeInsightsTileId("blutdruck")).toBe("blood-pressure");
+
+    for (const id of ["toString", "constructor", "__proto__"]) {
+      expect(normalizeInsightsTileId(id)).toBe(id);
+    }
+  });
+});
+
 describe("insights-layout v2 — section id universe", () => {
   it("carries exactly the default sections in render order", () => {
     expect([...INSIGHTS_SECTION_IDS]).toEqual([

src/lib/insights-layout.ts

@@ -87,7 +87,9 @@ export const ACCEPTED_INSIGHTS_TILE_IDS = [
  * resolver's known-id filter drops anything truly unrecognised.
  */
 export function normalizeInsightsTileId(id: string): string {
-  return LEGACY_INSIGHTS_TILE_ID_ALIASES[id] ?? id;
+  return Object.hasOwn(LEGACY_INSIGHTS_TILE_ID_ALIASES, id)
+    ? LEGACY_INSIGHTS_TILE_ID_ALIASES[id]
+    : id;
 }
 
 /**