enforce_latched_approval_note swallowed every get_workflow error via
.ok(), collapsing a transient DB error to None and skipping the latch
check. A PgPool blip during channel resolution would let a plaintext
approval note reach a latched DM — the leak this PR closes, reopened on
the security boundary itself. Match enforce_latched_body's posture:
NotFound passes (no resolvable channel, cannot be latched), any other
DbError is fail-visible.
Co-authored-by: Will Pfleger <pfleger.will@gmail.com>
Signed-off-by: Will Pfleger <pfleger.will@gmail.com>