Repacking fails on Windows when the ILRepack command line exceeds the length limit #216

Repacking an add-in succeeds on Windows whatever the number of merged assemblies and the length of the project path.

The SDK passes every input assembly and every reference folder to ILRepack as a full path on the command line.
Windows rejects a command line longer than 32,767 characters, and a Revit add-in that merges about 90 assemblies reaches that limit under a long directory.

Steps to reproduce

1. Take an add-in with IsRepackable enabled whose publish folder contains about 90 assemblies.
2. Place the solution under a directory whose path is about 150 characters long.
3. Build a release configuration with publishing enabled, for example dotnet build -c Release.R25.

Expected behavior

• The build merges the assemblies into the add-in assembly at any path length.

Actual behavior

• The build fails in RepackAddinFiles:

  Nice3point.Revit.Repack.targets(66,9): error MSB3073: The command ""…\ilrepack\2.0.48\tools\ILRepack.exe" /union /illink /parallel /noRepackRes /out:… /lib:… …" exited with code 9020.
  

• Exit code 9020 means "The system cannot execute the specified program".

• The command line of the failing build has 37,349 characters, and repeats the root path 113 times.

• The same add-in under a 45-character root produces about 25,300 characters, close to the limit already.

• With a shorter command line, the same build fails inside ILRepack with System.IO.PathTooLongException. On Windows, ILRepack.exe runs on .NET Framework, which rejects a path longer than 260 characters, and 65 of the 95 input paths exceed it.

Environment

• Nice3point.Revit.Sdk 6.3.1
• ILRepack 2.0.48
• Windows 11, .NET SDK 10.0.112, Revit 2025 configuration (net8.0-windows)