MUST be used whenever fixing security issues in a Flows app, or before shipping any feature that handles credentials, user input, or external data. This skill finds AND fixes security problems — it does not just report them. Do NOT skip this when the user asks for a security fix, security hardening, or vulnerability remediation — run every step in order. Triggers: security, security fix, security hardening, vulnerability, XSS, injection, credentials, secrets, auth, authentication, authorization, token, sensitive data, input validation, CORS, CSP, dependency audit.