Reduce the number of .dll files in output directory

Right now, every `.dll` in from project references ends up in the output folder.

Is there a way to prevent most of them from being copied while still being able to run it from `.exe`?

Start by inspecting the project-reference and MSBuild output behavior that places .dll files beside the .exe. Determine which dependencies are required at runtime, then verify that the output contains fewer copied assemblies while the generated .exe still runs successfully.

Written by the indexing model from the issue text.