Facade Effect part — only yield* MountFn(...) commands. Keeping the
generator homogeneous lets TS infer R cleanly. The pure builders
(album/story uploaders, which return { upload, metadata } workflow
objects rather than Effects) are merged in at runtime via PostingBuilders.
Facade Effect part — only
yield* MountFn(...)commands. Keeping the generator homogeneous lets TS infer R cleanly. The pure builders (album/story uploaders, which return{ upload, metadata }workflow objects rather than Effects) are merged in at runtime viaPostingBuilders.