License Catch3's Progmasoft files under LGPL-3.0-or-later

Every Progmasoft-authored file moves from MPL-2.0 WITH
AdditionRef-Progmasoft-Exception-2.0 to LGPL-3.0-or-later, from 0.5.0
on. Catch2-originated files keep BSL-1.0, and the vendored yyjson and
pugixml keep MIT.

- LICENSES/ holds the LGPL-3.0 text and the GPL-3.0 text it builds on,
  both as published by the FSF; the MPL-2.0 and Progmasoft Exception
  texts go, since no file uses them any more.
- Five files that came from Catch2 and were rewritten by Progmasoft
  (.clang-format, the issue and pull request templates, SECURITY.md)
  keep Catch2's notice next to Progmasoft's and say
  LGPL-3.0-or-later AND BSL-1.0.
- //tools:check expects the new header of Progmasoft files; the
  amalgamation notes say LGPL-3.0-or-later and the amalgamated files
  are regenerated; meson's project license is BSL-1.0 and
  LGPL-3.0-or-later.
- README gains a License section; LICENSES/README.md, contributing.md
  and progmasoft-catch3.md describe the new split and that releases
  before 0.5.0 keep the license they were published under.

Every commit to Progmasoft's files since the fork is the maintainer's.

Claude-Session: https://claude.ai/code/session_01Ji7xZMYjc4zankoc7hGBE1

84 files changed, 84 insertions, 84 deletions

diff --git a/src/Progmasoft/BUILD.bazel b/src/Progmasoft/BUILD.bazel
index 71f358ab..76639717 100644
--- a/src/Progmasoft/BUILD.bazel
+++ b/src/Progmasoft/BUILD.bazel
@@ -1,5 +1,5 @@
 # Copyright (c) 2026 Progmasoft.
-# SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+# SPDX-License-Identifier: LGPL-3.0-or-later
 load("@bazel_skylib//rules:expand_template.bzl", "expand_template")
 load("@rules_cc//cc:defs.bzl", "cc_library")
 
diff --git a/src/Progmasoft/Catch3.hpp b/src/Progmasoft/Catch3.hpp
index 2e04782a..0c5227c0 100644
--- a/src/Progmasoft/Catch3.hpp
+++ b/src/Progmasoft/Catch3.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 // Convenience include: prefer narrow headers when compile time matters.
diff --git a/src/Progmasoft/Catch3/Assertions.hpp b/src/Progmasoft/Catch3/Assertions.hpp
index b3b5ba01..6fe02012 100644
--- a/src/Progmasoft/Catch3/Assertions.hpp
+++ b/src/Progmasoft/Catch3/Assertions.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <Progmasoft/Catch3/Message.hpp>
diff --git a/src/Progmasoft/Catch3/Detail/InvalidArgument.hpp b/src/Progmasoft/Catch3/Detail/InvalidArgument.hpp
index e85900f0..f3ff5c7e 100644
--- a/src/Progmasoft/Catch3/Detail/InvalidArgument.hpp
+++ b/src/Progmasoft/Catch3/Detail/InvalidArgument.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <cstdio>
diff --git a/src/Progmasoft/Catch3/Detail/Sequence.hpp b/src/Progmasoft/Catch3/Detail/Sequence.hpp
index eea7762a..920b11cd 100644
--- a/src/Progmasoft/Catch3/Detail/Sequence.hpp
+++ b/src/Progmasoft/Catch3/Detail/Sequence.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <cstddef>
diff --git a/src/Progmasoft/Catch3/Detail/TypeTraits.hpp b/src/Progmasoft/Catch3/Detail/TypeTraits.hpp
index 208fc035..3f759ac3 100644
--- a/src/Progmasoft/Catch3/Detail/TypeTraits.hpp
+++ b/src/Progmasoft/Catch3/Detail/TypeTraits.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <type_traits>
diff --git a/src/Progmasoft/Catch3/ForAll.hpp b/src/Progmasoft/Catch3/ForAll.hpp
index c510db28..e11525dc 100644
--- a/src/Progmasoft/Catch3/ForAll.hpp
+++ b/src/Progmasoft/Catch3/ForAll.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <Progmasoft/Catch3/Property.hpp>
diff --git a/src/Progmasoft/Catch3/Generator.hpp b/src/Progmasoft/Catch3/Generator.hpp
index 520696d1..560e8e4e 100644
--- a/src/Progmasoft/Catch3/Generator.hpp
+++ b/src/Progmasoft/Catch3/Generator.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <Progmasoft/Catch3/Detail/InvalidArgument.hpp>
diff --git a/src/Progmasoft/Catch3/Generators/Boolean.hpp b/src/Progmasoft/Catch3/Generators/Boolean.hpp
index 8f3e3a1c..9daf181b 100644
--- a/src/Progmasoft/Catch3/Generators/Boolean.hpp
+++ b/src/Progmasoft/Catch3/Generators/Boolean.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <Progmasoft/Catch3/Generator.hpp>
diff --git a/src/Progmasoft/Catch3/Generators/Element.hpp b/src/Progmasoft/Catch3/Generators/Element.hpp
index 5d372bba..f3a9c2f2 100644
--- a/src/Progmasoft/Catch3/Generators/Element.hpp
+++ b/src/Progmasoft/Catch3/Generators/Element.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <Progmasoft/Catch3/Detail/TypeTraits.hpp>
diff --git a/src/Progmasoft/Catch3/Generators/Integer.hpp b/src/Progmasoft/Catch3/Generators/Integer.hpp
index 4d4e181b..da262567 100644
--- a/src/Progmasoft/Catch3/Generators/Integer.hpp
+++ b/src/Progmasoft/Catch3/Generators/Integer.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <Progmasoft/Catch3/Detail/TypeTraits.hpp>
diff --git a/src/Progmasoft/Catch3/Generators/Text.hpp b/src/Progmasoft/Catch3/Generators/Text.hpp
index fc76fd6a..ce133053 100644
--- a/src/Progmasoft/Catch3/Generators/Text.hpp
+++ b/src/Progmasoft/Catch3/Generators/Text.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <Progmasoft/Catch3/Detail/Sequence.hpp>
diff --git a/src/Progmasoft/Catch3/Generators/Tuple.hpp b/src/Progmasoft/Catch3/Generators/Tuple.hpp
index 2cd5d225..1f83eb13 100644
--- a/src/Progmasoft/Catch3/Generators/Tuple.hpp
+++ b/src/Progmasoft/Catch3/Generators/Tuple.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <Progmasoft/Catch3/Generator.hpp>
diff --git a/src/Progmasoft/Catch3/Generators/Vector.hpp b/src/Progmasoft/Catch3/Generators/Vector.hpp
index 658f186b..15e58d1a 100644
--- a/src/Progmasoft/Catch3/Generators/Vector.hpp
+++ b/src/Progmasoft/Catch3/Generators/Vector.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <Progmasoft/Catch3/Detail/Sequence.hpp>
diff --git a/src/Progmasoft/Catch3/Mock.hpp b/src/Progmasoft/Catch3/Mock.hpp
index 59ad8bb9..dac59861 100644
--- a/src/Progmasoft/Catch3/Mock.hpp
+++ b/src/Progmasoft/Catch3/Mock.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <Progmasoft/Catch3/Internal/Enforce.hpp>
diff --git a/src/Progmasoft/Catch3/Property.hpp b/src/Progmasoft/Catch3/Property.hpp
index 5962eaaf..4e9087ea 100644
--- a/src/Progmasoft/Catch3/Property.hpp
+++ b/src/Progmasoft/Catch3/Property.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once
 
 #include <Progmasoft/Catch3/Detail/TypeTraits.hpp>
diff --git a/src/Progmasoft/Catch3/Random.hpp b/src/Progmasoft/Catch3/Random.hpp
index 65366c9a..614742e7 100644
--- a/src/Progmasoft/Catch3/Random.hpp
+++ b/src/Progmasoft/Catch3/Random.hpp
@@ -1,5 +1,5 @@
 // Copyright (c) 2026 Progmasoft.
-// SPDX-License-Identifier: MPL-2.0 WITH AdditionRef-Progmasoft-Exception-2.0
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #pragma once