Initial implementation of songbook toolset

Kotlin/JVM multi-module project for generating a scout songbook PDF
from ChordPro-format text files. Includes ChordPro parser, layout engine
with greedy spread packing for double-page songs, OpenPDF renderer,
CLI (Clikt), Compose Desktop GUI, and 5 sample songs.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

settings.gradle.kts

@@ -0,0 +1,25 @@
+rootProject.name = "songbook"
+
+pluginManagement {
+    repositories {
+        gradlePluginPortal()
+        maven("https://maven.pkg.jetbrains.space/public/p/compose/dev")
+        google()
+    }
+}
+
+dependencyResolutionManagement {
+    repositories {
+        mavenCentral()
+        maven("https://maven.pkg.jetbrains.space/public/p/compose/dev")
+        google()
+    }
+}
+
+include("model")
+include("parser")
+include("layout")
+include("renderer-pdf")
+include("app")
+include("cli")
+include("gui")