Act as a security reviewer for this LOCAL training project. Read lab.mjs and
lab.test.mjs before proposing changes. The actor must come from verified server
authentication. Map the invoice owner, tenant boundary and finance_admin exception.
Produce a table: claim, exact file/line, required attacker capability, affected
data, existing test and missing evidence. Separate confirmed findings from
hypotheses. Check same-tenant and cross-tenant cases, anonymous users and missing
fields. Do not assume that a hidden button or an unpredictable ID is authorization.
Do not contact a live service or change files yet.
