An external bundle keeps the ids its patch declares. composeProfileStack
decides ownership before anything mounts: built-in and boot-staged layers
claim first and a duplicate among them fails the boot, a contained bundle
that collides is left out whole, a user-layer insert of a taken id is
dropped, and every row left out is a `conflict` record in pluginFailures,
printed at boot and replaced on each recomposition. Boot, live reloads, and
--dump-config compose through the same function, so the dump shows the
contained groups the tree mounts.
The prefix made a user patch, a third-party manager's disabled rows, and a
bundle's own `!!js` id comparison miss silently; the note records both cases.
Yichen Jiang
5d742503ea