Added '.p7s' and '.pkcs7' to the list of well-known certificate-related extensions in the CertViewer plugin to support PKCS#7 detached signature files.
Marked the Plugin class as sealed to prevent inheritance. Commented out several file extensions in the WellKnownExtensions set, likely to restrict the plugin to more common certificate file types.
Added descriptive comments to each file extension in the WellKnownExtensions set to clarify the type and usage of each supported certificate-related file.
Introduces UI and logic to handle password-protected certificate files. The CertViewerControl now prompts for a password if needed, and attempts to reload the certificate with the provided password. Refactored certificate loading flow to support this feature.
Introduces QuickLook.Plugin.CertViewer for viewing certificate files (.pfx, .cer, .pem, etc.) in QuickLook. The plugin loads and displays certificate details or raw content, and is integrated into the solution and project files.
