feat(format): add formatRelativeTime (just now, Xm/Xh/Xd ago, MM/DD/YYYY)

src/lib/__tests__/format-date.test.ts

@@ -0,0 +1,36 @@
+import { describe, it, expect, beforeEach, afterEach, vi } from "vitest";
+import { formatRelativeTime } from "../format-date";
+
+describe("formatRelativeTime", () => {
+  beforeEach(() => {
+    vi.useFakeTimers();
+    vi.setSystemTime(new Date("2026-06-17T12:00:00Z"));
+  });
+  afterEach(() => {
+    vi.useRealTimers();
+  });
+
+  it("returns 'just now' for < 45s", () => {
+    expect(formatRelativeTime("2026-06-17T11:59:30Z")).toBe("just now");
+  });
+
+  it("returns '5m ago' for ~5 minutes", () => {
+    expect(formatRelativeTime("2026-06-17T11:55:00Z")).toBe("5m ago");
+  });
+
+  it("returns '2h ago' for ~2 hours", () => {
+    expect(formatRelativeTime("2026-06-17T10:00:00Z")).toBe("2h ago");
+  });
+
+  it("returns 'yesterday' for 1 day", () => {
+    expect(formatRelativeTime("2026-06-16T12:00:00Z")).toBe("yesterday");
+  });
+
+  it("returns '3d ago' for 3 days", () => {
+    expect(formatRelativeTime("2026-06-14T12:00:00Z")).toBe("3d ago");
+  });
+
+  it("returns MM/DD/YYYY for > 7 days", () => {
+    expect(formatRelativeTime("2026-06-01T12:00:00Z")).toBe("06/01/2026");
+  });
+});

src/lib/format-date.ts

@@ -36,4 +36,28 @@ export function formatTime(date: string | Date | null | undefined): string {
     hour: "2-digit",
     minute: "2-digit",
   });
+}
+
+/**
+ * "Just now" / "5m ago" / "2h ago" / "yesterday" / "3d ago" / MM/DD/YYYY.
+ *
+ * Used by the v2 admin Orders list (CardList time-ago badge) and any
+ * other place that needs a humanized, glanceable timestamp without
+ * pulling in a date library. Buckets are deliberately coarse — anything
+ * past a week is shown as the absolute date (MM/DD/YYYY) via formatDate.
+ */
+export function formatRelativeTime(input: string | Date | number): string {
+  const date = input instanceof Date ? input : new Date(input);
+  if (isNaN(date.getTime())) return "—";
+  const diffMs = Date.now() - date.getTime();
+  const diffSec = Math.round(diffMs / 1000);
+  if (diffSec < 45) return "just now";
+  const diffMin = Math.round(diffSec / 60);
+  if (diffMin < 60) return `${diffMin}m ago`;
+  const diffHr = Math.round(diffMin / 60);
+  if (diffHr < 24) return `${diffHr}h ago`;
+  const diffDay = Math.round(diffHr / 24);
+  if (diffDay === 1) return "yesterday";
+  if (diffDay < 7) return `${diffDay}d ago`;
+  return formatDate(date);
 }