Thin test-module wrapper that re-exports the assertions from
lib-management.dep-fetcher-test so they participate in
test-all-modules.sh aggregation (and therefore milestone-check).
kind=test-module rather than kind=module because production modules
cannot depend on test-role libs (engine_lib_resolver §role-constraint);
the test lib is role=test, so the runner must be a test-module.
Direct deps on dep-fetcher-test, dep-fetcher, and lib-core.git
because engine_lib_resolver does NOT expand transitive lib-deps —
each lib that init.lua / lib-init paths may require() must be in the
module's direct deps list.
