- Rename triangle.h to cork_triangle.h to avoid conflict with OpenFOAM's triangle.H
- Add header guards (#ifndef CORK_TRIANGLE_H) to prevent multiple inclusion
- Add REAL type definition to prevent compilation errors
- Update all references from triangle.h to cork_triangle.h in:
- src/isct/triangle.c
- src/mesh/mesh.isct.tpp
This resolves the triangulateio struct redefinition error when building
with OpenFOAM integration.