### What needs to get done Whenever the user is dropped into an interactive session (for example, when a build error occurs during `rockcraft pack --debug`), include all environment variables that would normally exist at that stage in the build. For example, if debugging happens because part `xyz` failed, you should have `CRAFT_PART_BUILD=/root/parts/xyz/build`, `CRAFT_PRIME=/root/prime`, etc ### Why it needs to get done For a user that is debugging, they want to debug exactly where the script left off. Without these environment variables, they need to set them manually to debug their own scripts. This is both tedious and leads to errors