Show each person's life stage, age, and partner in the inspector. Add per-stage fertility toggles and document the life cycle and birth conditions.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Persist calendar units and inclusive life-stage duration ranges, expose them in the UI, and preserve defaults when loading legacy snapshots. Date formatting now derives from calendar settings.
Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>