Question: The title should be self-explanitory, but just in case. I am trying to build an angular application which will be hosted on azure. Currently I am having some issues with using kestrel, so I would like to build the application in visual studio but without using any .net code (so no startup.cs or program.cs).
If the answer is plainly no, then I guess I will need to find another IDE that will do what I require.

Answer: 
Yes you can develop a SPA application without .net code in visual studio. **Visual studio code** is another **IDE** for cross platform development. 

Check out the example at [pluralsight](https://app.pluralsight.com/library/courses/angular-material-fundamentals/table-of-contents)
If you using node toolings to build you project you may want to try [Node.js Tools for Visual Studio](https://www.visualstudio.com/vs/node-js/)

It does have support for gulp/grunt tasks as well as it has integration with azure. The support is provided via custom project types.