Steps to reproduce:

1) Create a new HDRP template

2) Cteate Decal SG and open it

3) Create a VT sampler and connect it to Decal shader target

4) Observe "Unrecognized identifier 'DECLARE_STACK_CB' errors

4) If you assign this broken shader to a decal, remove all VT nodes, errors still keep popping up

Expected results: we either close input sockets (like it happens with custom interpolators and Vertex stage inputs) or throw a meaningful error