feat: Add ktlint to backend and format all files

legalconsenthub-backend/build.gradle

@@ -5,6 +5,7 @@ plugins {
     id 'io.spring.dependency-management' version '1.1.7'
     id 'org.jetbrains.kotlin.plugin.jpa' version '1.9.25'
     id 'org.openapi.generator' version '7.11.0'
+    id 'org.jlleitschuh.gradle.ktlint' version '13.1.0'
 }
 
 group = 'com.betriebsratkanzlei'
@@ -24,12 +25,6 @@ ext {
     openHtmlVersion = '1.0.10'
 }
 
-//dependencyManagement {
-//    imports {
-//        mavenBom 'eu.europa.ec.joinup.sd-dss:dss-bom:6.2'
-//    }
-//}
-
 dependencies {
     implementation 'com.fasterxml.jackson.module:jackson-module-kotlin'
     implementation 'org.jetbrains.kotlin:kotlin-reflect'
@@ -69,6 +64,16 @@ allOpen {
     annotation 'jakarta.persistence.Embeddable'
 }
 
+ktlint {
+    version = "1.5.0"
+    android = false
+    ignoreFailures = false
+    filter {
+        exclude("**/generated/**")
+        exclude { element -> element.file.path.contains("generated/") }
+    }
+}
+
 def generatedSourcesServerLegalconsenthubDir = "$buildDir/generated/server".toString()
 
 sourceSets {