windows.cpp and piped_proc.cpp reached windows.h through an imported
module's global module fragment, which does not cross the boundary.
LPT.cpp and zmq_input.cpp never had it at all - the first was in an
MSBuild batch that aborted before reaching it, the second is behind
WITH_ZMQ and has not been compiled by either CI job.
The earlier sweep only looked inside #ifdef _WIN32 blocks, but these
files are gated by CMake instead, so they have no such block.
The template-header propagation only walked files with a module
declaration, so EU07.cpp, windows.cpp, export_e3d_standalone.cpp and
every betterRenderer source were outside it - including the file with
main(). They reach cParser and friends through eu07.simcore and
instantiate their templates without the headers those bodies name.
Adds audit_modules.py, which checks the whole tree for the seven classes
this migration hit; all seven are clean now.
