FX.24 Student Program: verifying the email issues the license, no approval step

Only .edu / .ac.xx addresses were issued on the verify click; any other school address (cvut.cz) waited in Waiting for a staff Approve. Now every verified address is issued at once (active, welcome email, certificate). The Approve button is gone. New column student_licenses.upgrades_until (migration 121): set to a year on issue, moved on a year by each yearly check (confirm) on the SAME license, never a new one. Test bin/test-student-program.php (94). Not changed: an active student still has every version; the date is recorded, shown nowhere yet, and not yet read by the entitlement.