### What needs to get done - Redesign the state manager to track the partition where files are located - Redesign the `clean_shared_area()` function to remove the correct files from the list of tracked files from the `StateManager`'s state files The solution could leverage the data structures added by #664. ### Why it needs to get done If the same file exists in multiple partitions in a shared directory (`stage` or `prime`), cleaning doesn't work as expected. It will indiscriminately remove the file from all partitions. See [this test](https://github.com/canonical/craft-parts/pull/666/files#diff-0d1cfe4b47f2489eca5633ebe11745aadfdc8e83893f931870ab2399091b70d6R181-R201) for an example. This is because the `StateManager` does not track files per-partition.