Function resolve_mcp_families 

pub(crate) fn resolve_mcp_families(
    stored: Option<&[String]>,
) -> BTreeSet<McpFamily>

A stored selection’s resolved set: absent or empty means every family; names are canonicalised into wire order and de-duplicated. Unknown names cannot be written by either tool (both validate), but a hand-edited row could carry one - it is dropped loudly rather than widening or narrowing the surface silently.