POST /api/server/poweroff (dashboard login, POST only, the typed word KIKAPCSOLÁS / TURN OFF)
→ agent POST /host/poweroff (MinAgent 0.155.0; hidden for an older agent). The controller refuses
during its own backup/restore/app update; the agent's reasons are shown as household sentences.
„Kiszolgáló újraindítása" becomes „A Felhom újraindítása" and says it restarts the Felhom part;
/api/server/reboot is POST only (R-983). Tests red-proofed; parity fixtures regenerated on purpose.
