TankError: Could not find core configuration for environment – Core Cache Inconsistency After Failed Upgrade

The goal is to understand how to restore normal tank operation after a partially applied tk-core upgrade leaves the core descriptor cache in an inconsistent state, causing the error "Could not find core configuration for environment" on subsequent launches.

Constraints include the persistence of mismatched version descriptors in ~/.shotgun/tank/cache/core/ after a rollback via pip install, the absence of a documented tank subcommand to validate or rebuild this cache, and the potential for concurrent upgrades on shared NFS home directories to further corrupt bootstrap state. It is unclear whether any automated recovery procedure exists that avoids manual cache deletion.

Is there a supported tank subcommand to validate or rebuild the core descriptor cache? If not, what is the recommended procedure to safely recover without manually removing the cache directory? How does concurrent upgrade activity on NFS affect cache integrity, and what precautions should be taken to prevent recurrence?