fix(webui): align token usage heatmap

webui/src/tests/settings-view.test.tsx

@@ -119,6 +119,7 @@ const installedAnyGen = {
 function renderSettingsView(
   options: {
     initialSection?: "overview" | "apps" | "advanced" | "models";
+    initialSettings?: SettingsPayload;
     onSettingsChange?: (payload: SettingsPayload) => void;
     onNativeEngineRestart?: () => Promise<string>;
   } = {},
@@ -128,6 +129,7 @@ function renderSettingsView(
       <SettingsView
         theme="light"
         initialSection={options.initialSection ?? "apps"}
+        initialSettings={options.initialSettings}
         onToggleTheme={() => {}}
         onBackToChat={() => {}}
         onModelNameChange={() => {}}
@@ -140,6 +142,7 @@ function renderSettingsView(
 
 describe("SettingsView Apps catalog", () => {
   afterEach(() => {
+    vi.useRealTimers();
     vi.unstubAllGlobals();
   });
 
@@ -270,6 +273,44 @@ describe("SettingsView Apps catalog", () => {
     expect(screen.queryByText("Peak tokens")).not.toBeInTheDocument();
   });
 
+  it("aligns token activity days with the configured timezone", async () => {
+    vi.useFakeTimers();
+    vi.setSystemTime(new Date("2026-06-02T18:00:00Z"));
+    const payload: SettingsPayload = {
+      ...settingsPayload(),
+      agent: {
+        ...settingsPayload().agent,
+        timezone: "Asia/Shanghai",
+      },
+      usage: {
+        days: [
+          {
+            date: "2026-06-03",
+            prompt_tokens: 1200,
+            completion_tokens: 300,
+            cached_tokens: 500,
+            total_tokens: 1500,
+            requests: 2,
+          },
+        ],
+        total_tokens: 1500,
+        total_tokens_30d: 1500,
+        total_tokens_365d: 1500,
+        peak_day_tokens: 1500,
+        current_streak_days: 1,
+        longest_streak_days: 1,
+        active_days_30d: 1,
+        requests_30d: 2,
+        updated_at: "2026-06-03T00:00:00Z",
+      },
+    };
+    vi.stubGlobal("fetch", vi.fn(() => new Promise<Response>(() => {})));
+
+    renderSettingsView({ initialSection: "overview", initialSettings: payload });
+
+    expect(screen.getByLabelText("2026-06-03: 1.5K tokens, 2 requests")).toBeInTheDocument();
+  });
+
   it("shows context window options in model settings", async () => {
     vi.stubGlobal(
       "fetch",