fixed danmar#365 - do not treat standards with empty define string as…

… unknown (danmar#367)

clang-tidy.yml: updated to Clang 19 (danmar#359)

* clang-tidy.yml: updated to Clang 19

* .clang-tidy: disabled `boost-use-ranges` check

improved prerequisite checks for `__has_include` handling (danmar#286)

Fix danmar#335: object lifetime issue when reporting error (danmar#336)

Fix danmar#334 Do not assert when source file is missing (danmar#333)

Fix danmar#173 (Change license to 0BSD) (danmar#332)

avoid some redundant checks in `TokenList::readfile()` (danmar#324)