address greptile review feedback (greploop iteration 1)

- Fix P1: strip existing time component from expiration_date before
  appending end-of-day time to prevent NaN when backend returns full
  ISO timestamps
- Fix P2: append Z suffix for explicit UTC parsing
- Fix P2: restore global.Date in afterEach to prevent mock leaking
- Add test for full ISO timestamp input edge case

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

ui/litellm-dashboard/src/components/LicenseExpiryBanner.test.tsx

@@ -19,6 +19,7 @@ const mockGetLicenseInfo = vi.mocked(getLicenseInfo);
 
 const FIXED_NOW = new Date("2026-03-15T12:00:00Z").getTime();
 let realDateNow: () => number;
+let OrigDate: typeof Date;
 
 function makeLicense(expirationDate: string) {
   return {
@@ -34,9 +35,8 @@ describe("LicenseExpiryBanner", () => {
   beforeEach(() => {
     vi.clearAllMocks();
     realDateNow = Date.now;
+    OrigDate = Date; // capture before patching so we can restore in afterEach
     Date.now = () => FIXED_NOW;
-    // Also override new Date() with no args
-    const OrigDate = Date;
     const MockDate = class extends OrigDate {
       constructor(...args: any[]) {
         if (args.length === 0) {
@@ -70,6 +70,7 @@ describe("LicenseExpiryBanner", () => {
   });
 
   afterEach(() => {
+    global.Date = OrigDate;
     Date.now = realDateNow;
   });
 
@@ -145,6 +146,18 @@ describe("LicenseExpiryBanner", () => {
     expect(container.innerHTML).toBe("");
   });
 
+  it("should handle expiration_date with a full ISO timestamp (not just date-only)", async () => {
+    // Backend might return "2026-03-22T15:00:00Z" instead of "2026-03-22"
+    // The component should strip the time part and still render correctly.
+    mockGetLicenseInfo.mockResolvedValue(makeLicense("2026-03-22T15:00:00Z"));
+
+    render(<LicenseExpiryBanner />);
+
+    expect(
+      await screen.findByText("Enterprise License Expiring in 8 days")
+    ).toBeInTheDocument();
+  });
+
   it("should not render when has_license is false", async () => {
     mockGetLicenseInfo.mockResolvedValue({
       ...makeLicense("2026-03-20"),

ui/litellm-dashboard/src/components/LicenseExpiryBanner.tsx

@@ -23,7 +23,10 @@ export const LicenseExpiryBanner: React.FC = () => {
     return null;
   }
 
-  const expDate = new Date(licenseInfo.expiration_date + "T23:59:59");
+  // Strip any existing time component so we always get a valid date-only base,
+  // then append end-of-day in UTC to avoid timezone-dependent parsing.
+  const dateOnly = licenseInfo.expiration_date.split("T")[0];
+  const expDate = new Date(dateOnly + "T23:59:59Z");
   const now = new Date();
   const diffMs = expDate.getTime() - now.getTime();
   const daysRemaining = Math.ceil(diffMs / (1000 * 60 * 60 * 24));