Clarify storage limits and unify file metadata displays

apps/server/test/display-format.test.js

@@ -0,0 +1,24 @@
+import { test } from 'node:test';
+import assert from 'node:assert/strict';
+import { formatSize, formatAdminDate } from '../../web/src/displayFormat.js';
+
+test('shared display sizes use decimal KB below 1MB and switch only at MB/GB boundaries', () => {
+  for (const [bytes, expected] of [
+    [0, '0KB'],
+    [10, '1KB 미만'],
+    [1000, '1KB'],
+    [938000, '938KB'],
+    [999000, '999KB'],
+    [1000000, '1.0MB'],
+    [1100000, '1.1MB'],
+    [1000000000, '1.0GB'],
+    [1700000000, '1.7GB'],
+  ])
+    assert.equal(formatSize(bytes), expected);
+});
+
+test('admin dates include year and unambiguous Korea 24-hour time independent of host timezone', () => {
+  assert.equal(formatAdminDate(Date.parse('2026-10-22T02:02:00Z')), '2026년 10월 22일 11:02');
+  assert.equal(formatAdminDate(Date.parse('2026-10-21T15:02:00Z')), '2026년 10월 22일 00:02');
+  assert.equal(formatAdminDate(null), '확인 불가');
+});