Initial commit: PaperScan — lokale Android documentscanner voor Paperless-ngx

Native Kotlin/Compose app met CameraX + OpenCV randdetectie/perspectiefcorrectie,
multi-page PDF-export, en Paperless-ngx upload (of Android deelmenu). Alles lokaal.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

.gitignore

@@ -0,0 +1,16 @@
+*.iml
+.gradle/
+/local.properties
+/.idea/
+.DS_Store
+/build
+/app/build
+/captures
+.externalNativeBuild
+.cxx
+local.properties
+
+# Signing material must never be committed.
+keystore.properties
+*.jks
+*.keystore