Add OS matrix to include the latest Ubuntu, Windows, and macOS

.github/workflows/bld.yml

@@ -4,12 +4,13 @@ on: [push, pull_request, workflow_dispatch]
 
 jobs:
   build-bld-project:
-    runs-on: ubuntu-latest
-
     strategy:
       matrix:
         java-version: [17, 21, 24]
-        kotlin-version: [1.9.25, 2.1.10]
+        kotlin-version: [1.9.25, 2.1.20]
+        os: [ ubuntu-latest, windows-latest, macos-latest ]
+
+    runs-on: ${{ matrix.os }}
 
     steps:
       - name: Checkout source repository

examples/.idea/bld.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="BldConfiguration">
+    <events />
+  </component>
+</project>

examples/src/bld/java/com/example/ExampleBuild.java

@@ -34,7 +34,7 @@ public class ExampleBuild extends Project {
 
         repositories = List.of(MAVEN_LOCAL, MAVEN_CENTRAL, RIFE2_RELEASES);
 
-        final var kotlin = version(2, 1, 10);
+        final var kotlin = version(2, 1, 20);
         scope(compile)
                 .include(dependency("org.jetbrains.kotlin", "kotlin-stdlib", kotlin));
         scope(test)