ExperimentalExperimentalExperimentalExperimentalSelect a feature. Non-additive (default) replaces the selection —
single-select semantics; additive appends (multi-select).
Optionaladditive?: booleanExperimentalExperimentalToggle a feature's membership (map-click semantics).
Optionaladditive?: boolean
Framework-neutral external store behind HonuaSelectionProvider. Exposed so tests and non-React integrations can drive the same state.