admin
c48f95fe06
appbackup/userdata.go: EnsureUserdataDir (MkdirAll + explicit setgid Chmod 2775 +
chown gid 1000), UserdataSkeleton, EnsureUserdataSkeleton; linux chown/StatGID +
non-linux stubs. stackEnv injects USERDATA_PATH=<HDD_PATH>/userdata. Skeleton
pre-created on register + FileBrowser sync; deploy belt (composeExecCustomEnv on
'up') pre-creates every ${USERDATA_PATH} bind source. FileBrowser mounts userdata
(was appdata) — uid 1000 can now write into 2775 setgid. #8: migrate merge walk +
copyFile preserve source setgid+group so the convention survives MigrateAll.
Non-hollow tests incl. Linux setgid assertions + migration-preserve companion.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>