Chapter Membership Cubit

The Chapter Membership Cubit is a medium-complexity mobile-only component with a single dependency on the Multi-Chapter Membership Service, making its delivery timeline directly gated on that service's readiness. The cubit follows the Bloc pattern, so developers familiar with that architecture can implement and test it independently using unit tests with a mocked service layer. Key testing scenarios include the pending-changes commit flow, concurrent add/remove operations, and error state recovery. The component consumes state in both the Chapter Affiliations Panel and the Chapter Assignment Editor widgets, so changes to the ChapterMembershipState shape require coordinated widget updates — a point of integration risk that should be flagged in review.

ChapterMembershipCubit extends Cubit and is initialized with a MultiChapterMembershipService instance via constructor injection, making it easily testable with a mock. loadAffiliations() triggers an async fetch and emits loading → success or error states. addChapter() and removeChapter() apply changes to a local pending set without immediate persistence, allowing the UI to reflect optimistic state before commitChanges() flushes the delta to the service layer. This two-phase approach prevents unnecessary network calls during multi-step edits.

State emissions must cover all transitions: ChapterMembershipLoading, ChapterMembershipLoaded, ChapterMembershipError, and optionally ChapterMembershipValidationError for the 5-chapter constraint. Consumed by widgets using BlocBuilder or BlocConsumer; ensure context.read() is only called within a BlocProvider subtree.