DetectBlockersAsync was feeding TemplateAttribute.DataSourceReference
into the identifier scanner alongside script bodies, but that field is
an OPC UA node-address path (e.g. "ns=3;s=Tank.Level") owned by the
device, not script source. The dot delimiter inside the path tripped
the heuristic into flagging the address segment ("Tank", "Sensor",
"TestChildObject", "DevAppEngine") as a missing SharedScript or
ExternalSystem reference -- a 100% false-positive class on any
template catalog with OPC-UA-mapped attributes.
Drop the DataSourceReference scan entirely. Attribute.Value is still
scanned because it can carry a design-time default expression that
calls into runtime APIs. Add a regression test pinning the new behavior.
bae75be2d2