AvisLoader shortcut hijack: .backup rename + VLCAssistant VBScript launcher

This rule detects a specific persistence technique used by AvisLoader malware. It monitors for the creation of a .lnk.backup file alongside a corresponding .lnk shortcut modification in common shell locations (Desktop, Taskbar, etc.), coupled with the execution of wscript.exe or cscript.exe referencing the 'VLCAssistant' VBScript within a short time window. This sequence indicates an attempt to persist malicious activity by backing up existing shortcuts and replacing them with a launcher for the AvisLoader payload.