Block a user
Security headers middleware: CSP, Referrer-Policy, nosniff (#59)
Security: add security headers middleware (CSP, X-Frame-Options, Referrer-Policy)
fix #63: require deletion token on DELETE /api/pastes/{id}
[pentest] DELETE /api/pastes/{id} performs deletion without any authentication or deletion token
fix: atomic burn-after-read claim (#58)
Security: fix burn-after-read race (atomic conditional delete)
fix #63: require deletion token on DELETE /api/pastes/{id}
fix: input validation gaps (#68)
fix: atomic burn-after-read claim (#58)
Security headers middleware: CSP, Referrer-Policy, nosniff (#59)