Merge .NET 8 Web Apps

[kkamegawa]

This pull request includes the initial setup and configuration for a new ASP.NET Core MVC project targeting .NET 8.0. The most important changes include adding Razor Pages for error handling, home, and privacy, setting up the project structure and dependencies, and configuring the application pipeline.

Razor Pages Setup:

• Added Error.cshtml and its corresponding model Error.cshtml.cs to handle application errors. [1] [2]
• Added Index.cshtml and its corresponding model Index.cshtml.cs for the home page. [1] [2]
• Added Privacy.cshtml and its corresponding model Privacy.cshtml.cs for the privacy policy page. [1] [2]

Project Configuration:

• Created _Layout.cshtml for the shared layout and _ViewImports.cshtml for common directives. [1] [2]
• Configured Program.cs to set up the application pipeline and services.
• Added launchSettings.json for development environment configuration.

Static Assets and Styling:

• Added initial CSS and JavaScript files in the wwwroot directory for styling and client-side functionality. [1] [2]
• Included licenses for third-party libraries like Bootstrap and jQuery validation. [1] [2]