Expose actively bound actions via activeActions$

Editor assessment

`feat: expose actively bound actions via activeActions$` names the new observable and its contents precisely, legible to anyone working with the codebase's reactive patterns. Feat correctly marks new API surface, and no scope marks the store area, minor. No body explains what consumers do with the stream — the instructive use case — but the subject states the addition unambiguously. Imperative verb, no trailing period, compact. Clear, correct, and self-contained: a publishable example.