ENH: Test datatypes and values in Extern C interface
Integration tests for https://gitlab.indiscale.com/caosdb/customers/lfpb/management/-/issues/420 and caosdb-cpplib!13 (merged)
Almost solely whitespace changes that my clang-tidy performed, the only real changes concern the way strings are "returned" by the Extern C interface.
Edited by Florian Spreckelsen