Steps to update the project. These are more or less equivalent to what the WPILib project importer does but I find it nicer to know exactly what's changing.
- Download and install WPILib VS Code and tools from https://github.com/wpilibsuite/allwpilib/releases
- Open WPILib VS Code and create a new command-based template project
- Copy the GradleRIO plugin version from the template build.gradle to the robot build.gradle
- Make sure Java version in robot build.gradle is set to at least the version in the template
- Copy gradlew, gradlew.bat, and the entire gradle folder into the robot project
- Copy vendordeps/WPILibNewCommands.json into the robot project
- Update the projectYear in .wpilib/wpilib_preferences.json
- Update the rest of the vendor dependency JSON files by downloading them fromm the vendors' websites
- Fix any compilation errors in the robot code due to library changes