Update Failures 1 story

The Update Failures tag separates a concrete failure mode from broader Troubleshooting & Failure Modes troubleshooting. The diagnostic focus is updates that will not download, install, verify, or complete, including storage, network, package state, services, permissions, recovery data, and error codes relevant to the update mechanism. Troubleshooting stays specific to this failure mode, using measurements, logs, compatibility evidence, recovery options, or component checks only when they help confirm the cause.