Adds a `libreportal system reclaim` CLI command and an orange "Reclaim
space" button on /admin/config/system/storage (the v2 prune control the
page always hinted at).
Scope is deliberately SAFE: build cache + dangling (untagged) images
only (docker builder prune -f + docker image prune -f via the
rootless-aware runFileOp). It never touches volumes (app data) or
tagged/in-use images, so nothing an app relies on is removed.
Wiring mirrors system_update: a systemReclaim() action + system_reclaim
route case run the command verbatim through the task processor. The
button confirms via showConfirmation, shows a spinner, and re-reads
storage usage as the prune lands. Button styled with --status-warning to
match the Reclaimable stat it sits under, with a note clarifying scope.
Signed-off-by: librelad <librelad@digitalangels.vip>
3031c6cab9