- Added a common csharp rendering phase base to put shared assets of runtime and design time code gen.
- Added a new `DesignTimeIRPass` to setup the IR bits to provide accurate intellisense.
- Added a `CodeGenerationIntegrationTest` and moved the RuntimeCodeGenerationTests into it. This way we can re-use the cshtml files and it makes searching/running the tests easy..
- Updated how line mappings are calculated for some nodes.
#848