* feat(usage): retain last known quotas across failures and restarts

Reconcile failed provider snapshots with their last valid measurements, and restore a bounded redacted quota cache after verifying the configuration context. Label stale data and suppress its notifications and run-out forecasts.

Update usage/development guides, README, TODO, changelog and all translation catalogs. Verify strict make check, packaging and 51 synthetic Plasma smoke scenarios, including two-process KConfig restoration.

* fix(usage): bound stale retention and save late startup results

* fix(cache): enforce byte limits and strengthen restart checks

* fix(usage): preserve fresh service status during quota failures

* fix(ui): refine stale quota descriptions and Spanish labels