feat: setup dotnet project

[Povindu]

Frontend

• Moved the astro project into the ClientApp directory
• Removed BaseUrl in the Astro project
• Updated Astro local build script
• In development, the Astro frontend is proxied to the backend domain localhost:5125

Backend

• Created the ASP.NET project in the Server directory
• Created a test api endpoint to check api health (ex: localhost:5215/api/health)
• Set up routing redirects from [path].html to [path]
• Set up rewrites to serve relevant [path].html when users visit [path]

CICD

• Updated GitHub Pages workflow to only trigger on pushes and PR's created targeting the branch "deploy-to-github-pages"
• Updated paths to include ClientApp directory
• Set up a zip deployment to avoid issues arising when copying a large number of files.