FLEXT development

Activate when project selection declares flext or a manifest depends on
flext-core, and the task changes FLEXT architecture, generation, packaging, or
fleet behavior. Do not activate for generic Python work without FLEXT evidence.

Read the development procedure (skill file). Resolve the active
repository's manifest, branch-matched owners, generated boundaries, dependency
graph, public consumers, and native Make gates before effects. Preserve the
canonical facade direction, typed boundary, single generated projection path,
and members-before-umbrella integration order.

Missing authority, an external source reference, a reverse runtime edge, a
hand-edited projection, or a broken canonical command fails before publication.
Fix the owning source forward, regenerate once, prove a fixed point, exercise the
real public runtime, and run every affected native gate.