Unleash 5.4: Root-level access control, stale feature flag alerts, and flag limits

Unleash 5.4 introduces several management-focused features aimed at enhancing the governance of feature flags, including root-level access control, unified settings, alerts for stale feature flags, and flag limits. The update allows for more granular user permissions, enabling individual customization of permissions down to the root level for managing API tokens, addons, environments, context fields, and segments, which is particularly beneficial for large enterprises. The new unified settings option consolidates various edit options and includes a feature to limit the number of flags in a project to manage technical debt. Additionally, users can now add "potentially stale" events to notifications and adjust expiration dates for feature flags, with the option to set some flags not to expire. Fetching individual client tokens has been simplified, enhancing automation processes, and strategy variants have been moved to the strategy level in beta, inviting user feedback to refine the feature.