fix: harden widget query persistence and refresh indicator

Review follow-ups on the session query cache:

- Cache the per-payload size verdict and reuse a single TextEncoder. The
  persist subscription re-dehydrates the whole cache on every cache event,
  so every widget payload was being superjson-serialized several times per
  refresh cycle just to measure it.
- Skip the size measurement on the restore path. It runs before any query is
  allowed to fetch and the payload was already budgeted when it was written.
- Reject stored queries whose dataUpdatedAt is not a positive finite number;
  `undefined <= 0` is false, so those were hydrating with a NaN timestamp.
- Add `stop()` and tear the persister down before `queryClient.clear()`, so
  the clear cannot overwrite the saved snapshot with an empty cache.
- Remove every other scope's cache when a persister is created: signing out
  navigates away before the scope guard can react, which left the previous
  account's dashboard data in the tab.
- Remove the entry instead of storing an empty cache.

Refresh indicator:

- Make it decorative instead of an aria-live region; every widget refreshes
  on a timer, so it made assistive technology repeat "loading" forever.

Also broadens the e2e hydration-error matcher to production React's minified
error codes, hoists the single WidgetTimeProvider in ClientBoard, memoizes the
resolved local time zone, and drops the exports this branch made dead.

packages/widgets/src/clock/world-clock.ts

@@ -61,11 +61,6 @@ export interface WorldClockTime {
   dayDifference: number | null;
 }
 
-export const getResolvedLocalTimeZone = () => {
-  const timeZone = Intl.DateTimeFormat().resolvedOptions().timeZone;
-  return timeZone && isTimeZoneSupported(timeZone) ? timeZone : "UTC";
-};
-
 export const createWorldClockTime = ({
   city,
   now,

packages/widgets/src/common/widget-time-context.spec.tsx

@@ -10,7 +10,7 @@ import { useWidgetLocalTimeZone, WidgetTimeProvider } from "./widget-time-contex
 
 const TimeProbe = () => (
   <time>
-    {useWidgetNow("minute")?.toISOString() ?? "missing"}|{useWidgetLocalTimeZone() ?? "missing"}
+    {useWidgetNow("minute")?.toISOString() ?? "missing"}|{useWidgetLocalTimeZone()}
   </time>
 );
 

packages/widgets/src/common/widget-time-context.tsx

@@ -1,7 +1,7 @@
 "use client";
 
 import type { PropsWithChildren } from "react";
-import { createContext, useContext, useSyncExternalStore } from "react";
+import { createContext, useContext, useMemo, useSyncExternalStore } from "react";
 
 const WidgetTimestampContext = createContext<number | null>(null);
 const WidgetTimeZoneContext = createContext("UTC");
@@ -15,15 +15,22 @@ export const WidgetTimeProvider = ({
   children,
   initialTimestamp,
   initialTimeZone,
-}: PropsWithChildren<WidgetTimeProviderProps>) => (
-  <WidgetTimestampContext.Provider value={initialTimestamp}>
-    <WidgetTimeZoneContext.Provider value={getSupportedTimeZone(initialTimeZone)}>
-      {children}
-    </WidgetTimeZoneContext.Provider>
-  </WidgetTimestampContext.Provider>
-);
+}: PropsWithChildren<WidgetTimeProviderProps>) => {
+  const timeZone = useMemo(() => getSupportedTimeZone(initialTimeZone), [initialTimeZone]);
+
+  return (
+    <WidgetTimestampContext.Provider value={initialTimestamp}>
+      <WidgetTimeZoneContext.Provider value={timeZone}>{children}</WidgetTimeZoneContext.Provider>
+    </WidgetTimestampContext.Provider>
+  );
+};
 
 export const useWidgetInitialTimestamp = () => useContext(WidgetTimestampContext);
+
+/**
+ * Resolves to the browser time zone, but renders (and hydrates) with the time
+ * zone the server used so widgets can paint a time before hydration finishes.
+ */
 export const useWidgetLocalTimeZone = () => {
   const initialTimeZone = useContext(WidgetTimeZoneContext);
   return useSyncExternalStore(subscribeToTimeZone, getResolvedLocalTimeZone, () => initialTimeZone);
@@ -31,7 +38,15 @@ export const useWidgetLocalTimeZone = () => {
 
 const subscribeToTimeZone = () => () => undefined;
 
-const getResolvedLocalTimeZone = () => getSupportedTimeZone(Intl.DateTimeFormat().resolvedOptions().timeZone);
+// React calls the snapshot getter on every render of every consumer, and
+// resolving a time zone builds `Intl.DateTimeFormat` instances, so keep the
+// answer around: it cannot change without a new document.
+let resolvedLocalTimeZone: string | undefined;
+
+const getResolvedLocalTimeZone = () => {
+  resolvedLocalTimeZone ??= getSupportedTimeZone(Intl.DateTimeFormat().resolvedOptions().timeZone);
+  return resolvedLocalTimeZone;
+};
 
 const getSupportedTimeZone = (timeZone: string | undefined) => {
   if (!timeZone) return "UTC";

packages/widgets/src/index.tsx

@@ -3,9 +3,7 @@ import type { Loader } from "next/dynamic";
 import dynamic from "next/dynamic";
 import { Center, Loader as UiLoader } from "@mantine/core";
 
-import { objectEntries } from "@homarr/common";
 import type { IntegrationKind, WidgetKind } from "@homarr/definitions";
-import type { SettingsContextProps } from "@homarr/settings/creator";
 
 import * as anchorNote from "./anchor-note";
 import * as audioStats from "./audio-stats";
@@ -41,7 +39,6 @@ import * as notebook from "./notebook";
 import * as paperlessNgx from "./paperless-ngx";
 import * as patchmon from "./patchmon";
 import * as notifications from "./notifications";
-import type { WidgetOptionDefinition } from "./options";
 import * as releases from "./releases";
 import * as rssFeed from "./rssFeed";
 import * as smartHomeEntityState from "./smart-home/entity-state";
@@ -191,19 +188,3 @@ export type inferSupportedIntegrationsStrict<TKind extends WidgetKind> = (Widget
 }
   ? WidgetImports[TKind]["definition"]["supportedIntegrations"]
   : never[])[number];
-
-export const reduceWidgetOptionsWithDefaultValues = (
-  kind: WidgetKind,
-  settings: Pick<SettingsContextProps, "enableStatusByDefault" | "forceDisableStatus">,
-  currentValue: Record<string, unknown> = {},
-) => {
-  const definition = widgetImports[kind].definition;
-  const options = definition.createOptions(settings) as Record<string, WidgetOptionDefinition>;
-  return objectEntries(options).reduce(
-    (prev, [key, value]) => ({
-      ...prev,
-      [key]: currentValue[key] ?? value.defaultValue,
-    }),
-    {} as Record<string, unknown>,
-  );
-};

packages/widgets/src/time.ts

@@ -1,3 +1 @@
-export { WidgetTimeProvider, useWidgetInitialTimestamp, useWidgetLocalTimeZone } from "./common/widget-time-context";
-export { getNextWidgetTickDelay, useWidgetNow } from "./common/use-widget-now";
-export type { WidgetClockPrecision } from "./common/use-widget-now";
+export { WidgetTimeProvider } from "./common/widget-time-context";