Remove unnecessary fmt.Sprintf wrapping a string literal (staticcheck S1039), remove unused tempFileForPFX function, and clean up unused os import. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
Extract shared certutil helpers (CreatePFX, ParsePrivateKey, ComputeThumbprint, GenerateRandomPassword, ParseCertificatePEM) from IIS connector for reuse. Add WinCertStore connector (PowerShell Import-PfxCertificate, dual local/WinRM mode, configurable store/location, expired cert cleanup) and JavaKeystore connector (PEM→PKCS#12→keytool pipeline, JKS/PKCS12 support, shell injection prevention, path traversal protection). 53 new tests, all passing. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>