Function filesystem_grants_digest 

pub fn filesystem_grants_digest(fs: &FilesystemEntitlement) -> String

Digest of the filesystem half of a profile’s entitlements.

Narrower than card_digest on purpose: that one moves whenever any profile field does, so using it to flag “grants changed since this agent started” would raise a false alarm on an unrelated edit — and a status line that cries wolf is one people stop reading.