Scan.nextcloud.com: scan timestamp should display timezone (UTC)

Describe the issue
The “Scanned at” timestamp on scan.nextcloud.com results does not indicate
the timezone. Example: “Scanned at 2026-06-28 15:43:00” — it is ambiguous
whether this is UTC, server local time, or browser local time.

Expected behavior
Display the timezone explicitly, e.g.:
“Scanned at 2026-06-28 15:43:00 (UTC)”

This is a one-line fix (append the string " (UTC)" to the timestamp) that
eliminates any ambiguity for users in non-UTC timezones.

Actual behavior
No timezone indicator is shown. Users in non-UTC timezones (e.g. UTC+3)
may assume the time is local and get confused.

Steps to reproduce

  1. Scan any Nextcloud instance at https://scan.nextcloud.com
  2. Check the “Scanned at” timestamp in the result page
  3. No timezone is indicated

Nextcloud version scanned: 33.0.5.1
Browser: [your browser]
OS: [your OS]