Remediate security vulnerabilities by finding safe upgrade paths. Use when the user says "fix this vulnerability", "how do I fix CVE-XXXX", "remediate this finding", "patch this vuln", "endor fix", or wants step-by-step fix instructions for a specific CVE, finding, or vulnerable package. Can apply fixes automatically. Do NOT use for general scanning (/endor-scan) or just viewing vulnerability info (/endor-explain).