The two vault knobs become editable where operators already work: the
app-settings card gains the per-file upload cap (MB, 1-100, mirrors the
hard server ceiling) and the default per-account storage quota (GB,
commit-on-blur with clamped conversion to bytes); the user edit form
gains the per-user quota override (GB, empty = instance default). The
admin users list now carries the override so the form can show it.
Refs: document-vault plan W3-T7