Replace the create_fee_type/create_cycle helpers duplicated across 18/8
membership-fee test files with a single shared definition in Mv.Fixtures,
reconciling the divergent local signatures (including the reversed
argument order) into one superset so behavior is unchanged.
- Replace Enum.map |> Enum.join with Enum.map_join for efficiency
- Extract helper functions to reduce nesting depth from 4 to 2
- Rename is_current_cycle? to current_cycle? following Elixir conventions
- Implemented regenerate_cycles_on_type_change helper in Member resource
- Cycles that haven't ended yet (cycle_end >= today) are deleted and regenerated
- Paid and suspended cycles remain unchanged (not deleted)
- CycleGenerator reloads member with new membership_fee_type_id
- Adjusted tests to work with current cycles only (no future cycles)
- All integration tests passing
Phase 4 completed: Cycle regeneration on type change
