Function ownerless_readable 

pub fn ownerless_readable(
    operator_flag: Option<bool>,
    active_keys: usize,
) -> bool

Whether an index with no ownership record (“legacy”) may be read by an authenticated key — the rule the module doc states, kept as one pure decision so both branches are testable without a server.

operator_flag is the operator’s ruling (CODETOPO_DENY_OWNERLESS_INDEXES): Some(true) denies always, Some(false) allows always. Unset (None), the default denies once the key store holds more than one active key and allows while it holds at most one — the single-operator self-hosted case the legacy posture exists for.