2f27a363d5
This is D5's precondition and it is now met. An app's namespace root IS its backup root: namespaceRoot returns a non-system drive path as-is, so the recovery unit lands at <HDD_PATH>/backups/primary/<stack>/. On a NAS that sits inside the share, which FileBrowser binds WHOLE — share root, :rslave, download:true. The bind was NOT narrowed, and establishing why inverted the fix. The share-root :rslave bind is load-bearing (a 2026-07-22 probe proved an in-container access through it wakes the idle automount trigger), and scoping is undefinable anyway: apps on a share store at <share>/<app>, there is no userdata/ layer, and creating one would write Felhom convention onto a customer's own NAS, which R-67 forbids. So the browsing surface cannot be narrowed and the backup tree must never be placed under it. Operator ruling: refuse the placement, keep the browse bind. Tier 2 already refuses network targets for this reason (F-6C-1). Nothing stranded: zero apps on network storage across all six hub customers including Peti. R-67's browse capability is byte-identical. FIVE surfaces, not the four the register named — settings.RefuseAsAppNamespace is the single predicate. The deploy POST is the real boundary (it accepts any caller-supplied HDD_PATH; DeployStack validates only os.Stat). Surface 4, handleStorageDecommission mode=migrate, guarded only its SOURCE, so a whole namespace could be decommissioned ONTO a NAS — that one is not in the register. Fails closed: /mnt/felhom-drives holds both kinds, Kind exists only on a registered path, so an unregistered path under that root refuses. Supersedes README's "NAS backup locality — decision A" (v0.118.0). 9 tests, all non-effect (nil stackMgr, so a guard that misses panics rather than passing). 4 red-proofs, each mutation asserted to have landed. Suite rc=0, 27 packages, 0 FAIL. vet rc=0. Template + emoji gates OK.