Added sanitization to report_path_filename and enhanced authentication cookie

[winters0x64]

Proposed change

Set the authentication cookie's SameSite attribute to Lax by default to mitigate CSRF attacks, particularly during the grace period of Chrome's automatic Lax implementation.

Added input sanitization for the report_path_filename parameter in the /new/scan endpoint to prevent attempts to overwrite system files.

Type of change

• New core framework functionality
• Bugfix (non-breaking change which fixes an issue)
• Code refactoring without any functionality changes
• New or existing module/payload change
• Localization improvement
• Dependency upgrade
• Documentation improvement

Checklist

• I've followed the contributing guidelines
• I've run make pre-commit, it didn't generate any changes
• I've run make test, all tests passed locally