GHSA-W7W5-5GCP-38RW nebula-mesh: Web UI and API responses lack security headers (CSP, X-Frame-Options, HSTS, etc.)

None of the response paths in internal/web/ or internal/api/ set the standard browser-security headers. grep for Content-Security-Policy, X-Frame-Options, Strict-Transport-Security, X-Content-Type-Options, Referrer-Policy returns zero matches across the codebase. Impact The admin UI signs CA...