Say C++17 everywhere the project describes itselfchore/cpp17-descriptions

The move to C++17 left a trail of older claims. The Runner's own
.clang-format still said c++20; the result is byte for byte the same under
either value. Premake and Xmake still compiled the library as C++20 and
the main library as C++14, which meant their CI jobs were not testing the
language the project promises. Both now use C++17 for every target.

The rest is text: the Meson pkg-config description claimed C++14, comments
in the CMake and Meson files explained requirements that no longer exist,
.clang-tidy gave C++14 as the reason for two exclusions, issue templates
asked for C++20 samples, and the example headers named -std=c++14 and
catch2-with-main. The release notes and the migration guide state the
C++17 minimum. Doxygen's brief called the project "Catch2's test API",
which presents it as Catch2. Meson declared only BSL-1.0; it now names both
licenses of the tree. The amalgamated files are regenerated.

3 files changed, 4 insertions, 4 deletions

diff --git a/extras/catch_amalgamated.cpp b/extras/catch_amalgamated.cpp
index 3151faf3..7556181e 100644
--- a/extras/catch_amalgamated.cpp
+++ b/extras/catch_amalgamated.cpp
@@ -7,7 +7,7 @@
 // SPDX-License-Identifier: BSL-1.0
 
 //  Catch3 v0.3.0, on the Catch2 v3.16.1 engine
-//  Generated: 2026-10-31 20:20:20.891771
+//  Generated: 2026-11-01 00:25:29.768099
 //  ----------------------------------------------------------
 //  This file is an amalgamation of multiple different files.
 //  You probably shouldn't edit it directly.
diff --git a/extras/catch_amalgamated.hpp b/extras/catch_amalgamated.hpp
index f26b0811..513c91ae 100644
--- a/extras/catch_amalgamated.hpp
+++ b/extras/catch_amalgamated.hpp
@@ -7,7 +7,7 @@
 // SPDX-License-Identifier: BSL-1.0
 
 //  Catch3 v0.3.0, on the Catch2 v3.16.1 engine
-//  Generated: 2026-10-31 20:20:20.604513
+//  Generated: 2026-11-01 00:25:29.668428
 //  ----------------------------------------------------------
 //  This file is an amalgamation of multiple different files.
 //  You probably shouldn't edit it directly.
@@ -5942,7 +5942,7 @@ namespace Detail {
 namespace Catch {
 
     namespace Detail {
-        // This was added in C++20, but we require only C++14 for now.
+        // This was added in C++20, but we require only C++17.
         template <typename T>
         using RemoveCVRef_t = std::remove_cv_t<std::remove_reference_t<T>>;
     }
diff --git a/extras/catch_amalgamated_third_party.hpp b/extras/catch_amalgamated_third_party.hpp
index 6a48d4dd..353e0009 100644
--- a/extras/catch_amalgamated_third_party.hpp
+++ b/extras/catch_amalgamated_third_party.hpp
@@ -1,5 +1,5 @@
 // Catch3 v0.3.0: yyjson and pugixml for catch_amalgamated.cpp
-// Generated: 2026-10-31 20:20:21.165039
+// Generated: 2026-11-01 00:25:29.854771
 // ----------------------------------------------------------
 // This file is an amalgamation of src/Progmasoft/Runner/Yyjson.inl,
 // src/Progmasoft/PugiXml.inl and the libraries they include from