Sibling shares source for the local cross-drive tier. Reuses the tier2Mirror seam,
selectTier2TargetFrom (narrow source-drive seam extracted from selectTier2Target),
tier2ReconcileRoots (pure extraction), tier2SafeRemove, the marker-LAST discipline
and the recordTier2* helpers. Per-app paths are untouched.
- shares_payload.go: deterministic _shares-manifest.json + best-effort passdb capture
- tier2_shares.go: per-source-drive legs -> cross-drive target, payload, marker LAST
- infra.SambaContainerName/SambaPassdbVolume/Mount: single source of truth for the
container identity (renderer, stacks execs, backup execs, monitor all read it)
- RESERVED-NAME finding: ValidateSMBShareName did NOT exclude a leading underscore,
so "_shares" was an accepted share name. Now refused; RunAllTier2 additionally
skips a "_shares" stack loudly as defense in depth.
- fix: shareSourceDrive returned a slash-normalised path, which made the target
selector's source-drive equality check miss (a group could target its own drive)
SMBSettings + SMBShare registry in settings (password never stored — only UserSet);
NetBIOS-safe name validation. Pure infra renderers: RenderSambaConfig (hardened
global block: SMB2 floor, bind interfaces only=lo eth0, disable netbios=no, force
user block) + RenderSambaCompose (network_mode host, pinned image, :ro bind for
read-only shares, passdb volume). Exact smb.conf golden + CRUD/validation tests.