fix(web): ignore malformed dashboard tile snapshots

apps/web/src/App.tsx

@@ -45,6 +45,11 @@ type DashboardTileResponse =
       state: "not_found";
       tile: DashboardTileReference;
       message: string;
+    }
+  | {
+      state: "disabled";
+      tile: DashboardTileReference;
+      message: string;
     };
 
 type DashboardTileHydrationResult = "aborted" | "failed" | "ready";

apps/web/src/lib/client/dashboard-refresh.test.ts

@@ -164,6 +164,15 @@ describe("dashboard refresh lifecycle", () => {
       },
       schemaVersion: "dashboard.v1",
     });
+    store.saveTile({
+      currentRevisionId: "revision-a",
+      response: {
+        state: "disabled",
+        tile: { kind: "module", id: "disabled-module" },
+        message: "Disabled",
+      },
+      schemaVersion: "dashboard.v1",
+    });
 
     now = 61_000;
 
@@ -193,6 +202,53 @@ describe("dashboard refresh lifecycle", () => {
       schemaVersion: "dashboard.v1",
     })).toEqual([]);
   });
+
+  test("ignores malformed stored tile snapshots", () => {
+    const storage = createMemoryStorage();
+    storage.setItem(
+      "dimensionlab.dashboard.tiles.v1",
+      JSON.stringify({
+        currentRevisionId: "revision-a",
+        schemaVersion: "dashboard.v1",
+        tiles: [
+          {},
+          {
+            item: { id: "infra-ram", detail: "live" },
+            savedAt: 1_000,
+            tile: { kind: "telemetry", id: "infra-ram" },
+          },
+          {
+            item: { id: "broken-detail", detail: 42 },
+            savedAt: 1_000,
+            tile: { kind: "telemetry", id: "broken-detail" },
+          },
+        ],
+        version: 1,
+      }),
+    );
+
+    const store = createDashboardTileSnapshotStore(storage, {
+      now: () => 16_000,
+    });
+
+    expect(store.restore({
+      currentRevisionId: "revision-a",
+      schemaVersion: "dashboard.v1",
+    })).toEqual([
+      {
+        ageMs: 15_000,
+        response: {
+          state: "ready",
+          tile: { kind: "telemetry", id: "infra-ram" },
+          item: {
+            id: "infra-ram",
+            detail: "live - stale 15s",
+            severity: "stale",
+          },
+        },
+      },
+    ]);
+  });
 });
 
 async function waitFor(predicate: () => boolean) {

apps/web/src/lib/client/dashboard-refresh.ts

@@ -231,7 +231,12 @@ export function createDashboardTileSnapshotStore(
         return null;
       }
 
-      return payload as DashboardTileSnapshotPayload;
+      return {
+        currentRevisionId: payload.currentRevisionId,
+        schemaVersion: payload.schemaVersion,
+        tiles: payload.tiles.filter(isDashboardTileSnapshotRecord),
+        version: 1,
+      };
     } catch {
       return null;
     }
@@ -332,6 +337,51 @@ function dashboardTileSnapshotKey(tile: DashboardTileReference): string {
   return JSON.stringify(tile);
 }
 
+function isDashboardTileSnapshotRecord(
+  value: unknown,
+): value is DashboardTileSnapshotRecord {
+  if (!isSnapshotRecord(value)) return false;
+
+  return (
+    typeof value.savedAt === "number" &&
+    Number.isFinite(value.savedAt) &&
+    isDashboardTileReference(value.tile) &&
+    isDashboardTileSnapshotItem(value.item)
+  );
+}
+
+function isDashboardTileReference(
+  value: unknown,
+): value is DashboardTileReference {
+  if (!isSnapshotRecord(value) || typeof value.kind !== "string") return false;
+
+  switch (value.kind) {
+    case "telemetry":
+    case "module":
+      return typeof value.id === "string";
+    case "service":
+      return typeof value.groupId === "string" && typeof value.id === "string";
+    case "status":
+      return typeof value.stripId === "string" && typeof value.id === "string";
+    default:
+      return false;
+  }
+}
+
+function isDashboardTileSnapshotItem(
+  value: unknown,
+): value is DashboardTileSnapshotItem {
+  return (
+    isSnapshotRecord(value) &&
+    typeof value.id === "string" &&
+    (value.detail === undefined || typeof value.detail === "string")
+  );
+}
+
+function isSnapshotRecord(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value !== null;
+}
+
 function staleDashboardTileDetail(
   detail: string | undefined,
   ageMs: number,