chore: refactor Gradle config, standardize Kotlin MPP plugin usage, and update dependencies

- Unified plugin application across modules using `alias(libs.plugins.*)` instead of hardcoded IDs.
- Removed redundant JVM/JS source map tasks, improving Gradle and Docker build consistency.
- Updated dependencies, including `logback` and Webpack `copy-webpack-plugin`, and added contextual documentation.
- Added frontend architecture diagram in PlantUML (`docs/01_Architecture/Reference`), standardizing feature-core-shell dependencies.

frontend/core/auth/build.gradle.kts

@@ -1,8 +1,5 @@
-import org.jetbrains.kotlin.gradle.dsl.JvmTarget
-
 plugins {
-  // Fix for "Plugin loaded multiple times": Apply plugin by ID without version (inherited from root)
-  id("org.jetbrains.kotlin.multiplatform")
+  alias(libs.plugins.kotlinMultiplatform)
   alias(libs.plugins.composeMultiplatform)
   alias(libs.plugins.composeCompiler)
   alias(libs.plugins.kotlinSerialization)
@@ -13,11 +10,9 @@ version = "1.0.0"
 
 kotlin {
   jvm()
-
   js {
     binaries.library()
-    // CHANGED: Use nodejs() instead of browser() to minimize NodeJsRootPlugin conflicts in Docker
-    // while still satisfying the "configured for JS usage" requirement.
+    // Use nodejs() to minimize NodeJsRootPlugin conflicts in Docker
     nodejs()
   }
 
@@ -70,13 +65,3 @@ kotlin {
     }
   }
 }
-
-tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile> {
-  compilerOptions {
-    jvmTarget.set(JvmTarget.JVM_25)
-    freeCompilerArgs.addAll(
-      "-opt-in=kotlin.RequiresOptIn",
-      "-Xexpect-actual-classes"
-    )
-  }
-}

frontend/core/design-system/build.gradle.kts

@@ -1,21 +1,15 @@
 plugins {
-  // Fix for "Plugin loaded multiple times": Apply plugin by ID without version (inherited from root)
-  id("org.jetbrains.kotlin.multiplatform")
-  alias(libs.plugins.composeMultiplatform)
-  alias(libs.plugins.composeCompiler)
+  alias(libs.plugins.kotlinMultiplatform)
   alias(libs.plugins.kotlinSerialization)
+  alias(libs.plugins.composeCompiler)
+  alias(libs.plugins.composeMultiplatform)
 }
 
 kotlin {
   jvm()
-  js(IR) {
+  js {
     binaries.library()
-    // Re-enabled browser environment after Root NodeJs fix
-    browser {
-        testTask {
-            enabled = false
-        }
-    }
+    browser()
   }
 
   sourceSets {
@@ -25,9 +19,7 @@ kotlin {
       implementation(compose.material3)
       implementation(compose.ui)
       implementation(compose.components.resources)
-      implementation(libs.kotlinx.coroutines.core)
-      implementation(libs.kotlinx.serialization.json)
-      implementation(libs.kotlinx.datetime)
+      implementation(libs.bundles.kmp.common)
     }
   }
 }

frontend/core/domain/build.gradle.kts

@@ -1,7 +1,6 @@
 @file:OptIn(ExperimentalKotlinGradlePluginApi::class)
 
 import org.jetbrains.kotlin.gradle.ExperimentalKotlinGradlePluginApi
-import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 
 plugins {
   alias(libs.plugins.kotlinMultiplatform)
@@ -14,9 +13,9 @@ kotlin {
     binaries.library()
     // Re-enabled browser environment after Root NodeJs fix
     browser {
-        testTask {
-            enabled = false
-        }
+      testTask {
+        enabled = false
+      }
     }
   }
 
@@ -27,9 +26,4 @@ kotlin {
   }
 }
 
-tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile> {
-  compilerOptions {
-    jvmTarget.set(JvmTarget.JVM_25)
-    freeCompilerArgs.addAll("-opt-in=kotlin.RequiresOptIn")
-  }
-}
+// KMP Compile-Optionen sind jetzt zentral in der Root build.gradle.kts definiert

frontend/core/local-db/build.gradle.kts

@@ -3,8 +3,7 @@
 import org.jetbrains.kotlin.gradle.ExperimentalKotlinGradlePluginApi
 
 plugins {
-  // Fix for "Plugin loaded multiple times": Apply plugin by ID without version (inherited from root)
-  id("org.jetbrains.kotlin.multiplatform")
+  alias(libs.plugins.kotlinMultiplatform)
   alias(libs.plugins.kotlinSerialization)
   alias(libs.plugins.sqldelight)
 }
@@ -13,12 +12,7 @@ kotlin {
   jvm()
   js {
     binaries.library()
-    // Re-enabled browser environment after Root NodeJs fix
-    browser {
-        testTask {
-            enabled = false
-        }
-    }
+    browser()
   }
 
   sourceSets {
@@ -35,7 +29,7 @@ kotlin {
 
     jsMain.dependencies {
       implementation(libs.sqldelight.driver.web)
-      implementation(npm("@sqlite.org/sqlite-wasm", "3.51.1-build2"))
+      implementation(npm("@sqlite.org/sqlite-wasm", libs.versions.sqliteWasm.get()))
     }
 
     commonTest.dependencies {

frontend/core/navigation/build.gradle.kts

@@ -1,10 +1,8 @@
 /**
  * Dieses Modul definiert nur die Navigationsrouten.
- * Es ist noch simpler.
  */
 plugins {
-  // Fix for "Plugin loaded multiple times": Apply plugin by ID without version (inherited from root)
-  id("org.jetbrains.kotlin.multiplatform")
+  alias(libs.plugins.kotlinMultiplatform)
 }
 
 group = "at.mocode.clients.shared"
@@ -14,18 +12,13 @@ kotlin {
   jvm()
   js {
     binaries.library()
-    // Re-enabled browser environment after Root NodeJs fix
-    browser {
-        testTask {
-            enabled = false
-        }
-    }
+    browser()
   }
 
   sourceSets {
     commonMain.dependencies {
       // Depend on core domain for User/Role types used by navigation API
-      implementation(project(":frontend:core:domain"))
+      implementation(projects.frontend.core.domain)
     }
     commonTest.dependencies {
       implementation(libs.kotlin.test)

frontend/core/network/build.gradle.kts

@@ -1,11 +1,9 @@
 @file:OptIn(ExperimentalKotlinGradlePluginApi::class)
 
 import org.jetbrains.kotlin.gradle.ExperimentalKotlinGradlePluginApi
-import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 
 plugins {
-  // Fix for "Plugin loaded multiple times": Apply plugin by ID without version (inherited from root)
-  id("org.jetbrains.kotlin.multiplatform")
+  alias(libs.plugins.kotlinMultiplatform)
   alias(libs.plugins.kotlinSerialization)
 }
 
@@ -13,12 +11,7 @@ kotlin {
   jvm()
   js {
     binaries.library()
-    // Re-enabled browser environment after Root NodeJs fix
-    browser {
-        testTask {
-            enabled = false
-        }
-    }
+    browser()
   }
 
   sourceSets {
@@ -41,10 +34,3 @@ kotlin {
     }
   }
 }
-
-tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile> {
-  compilerOptions {
-    jvmTarget.set(JvmTarget.JVM_25)
-    freeCompilerArgs.addAll("-opt-in=kotlin.RequiresOptIn")
-  }
-}

frontend/core/sync/build.gradle.kts

@@ -1,19 +1,13 @@
 plugins {
-  // Fix for "Plugin loaded multiple times": Apply plugin by ID without version (inherited from root)
-  id("org.jetbrains.kotlin.multiplatform")
+  alias(libs.plugins.kotlinMultiplatform)
   alias(libs.plugins.kotlinSerialization)
 }
 
 kotlin {
   jvm()
-  js(IR) {
+  js {
     binaries.library()
-    // Re-enabled browser environment after Root NodeJs fix
-    browser {
-        testTask {
-            enabled = false
-        }
-    }
+    browser()
   }
 
   sourceSets {

frontend/features/ping-feature/build.gradle.kts

@@ -1,11 +1,8 @@
-import org.jetbrains.kotlin.gradle.dsl.JvmTarget
-
 /**
  * Dieses Modul kapselt die gesamte UI und Logik für das Ping-Feature.
  */
 plugins {
-  // Fix for "Plugin loaded multiple times": Apply plugin by ID without version (inherited from root)
-  id("org.jetbrains.kotlin.multiplatform")
+  alias(libs.plugins.kotlinMultiplatform)
   alias(libs.plugins.composeMultiplatform)
   alias(libs.plugins.composeCompiler)
   alias(libs.plugins.kotlinSerialization)
@@ -18,12 +15,7 @@ kotlin {
   jvm()
   js {
     binaries.library()
-    // Re-enabled browser environment after Root NodeJs fix
-    browser {
-        testTask {
-            enabled = false
-        }
-    }
+    browser()
   }
 
   sourceSets {
@@ -70,12 +62,3 @@ kotlin {
     }
   }
 }
-
-tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile> {
-  compilerOptions {
-    jvmTarget.set(JvmTarget.JVM_25)
-    freeCompilerArgs.addAll(
-      "-opt-in=kotlin.RequiresOptIn"
-    )
-  }
-}

frontend/shells/meldestelle-portal/build.gradle.kts

@@ -3,7 +3,6 @@
 
 import org.jetbrains.compose.desktop.application.dsl.TargetFormat
 import org.jetbrains.kotlin.gradle.ExperimentalKotlinGradlePluginApi
-import org.jetbrains.kotlin.gradle.dsl.JvmTarget
 import org.jetbrains.kotlin.gradle.targets.js.webpack.KotlinWebpackConfig
 
 /**
@@ -11,16 +10,13 @@ import org.jetbrains.kotlin.gradle.targets.js.webpack.KotlinWebpackConfig
  * setzt sie zu einer lauffähigen Anwendung zusammen.
  */
 plugins {
-  // Fix for "Plugin loaded multiple times": Apply plugin by ID without version (inherited from root)
-  id("org.jetbrains.kotlin.multiplatform")
+  alias(libs.plugins.kotlinMultiplatform)
   alias(libs.plugins.composeCompiler)
   alias(libs.plugins.composeMultiplatform)
   alias(libs.plugins.kotlinSerialization)
 }
 
 kotlin {
-  // Toolchain is now handled centrally in the root build.gradle.kts
-
   // JVM Target für Desktop
   jvm {
     binaries {
@@ -31,7 +27,7 @@ kotlin {
   }
 
   // JavaScript Target für Web
-  js(IR) {
+  js {
     browser {
       commonWebpackConfig {
         cssSupport { enabled = true }
@@ -43,7 +39,7 @@ kotlin {
 
         // Source Maps Optimierung für Docker Builds
         if (project.hasProperty("noSourceMaps")) {
-            sourceMaps = false
+          sourceMaps = false
         }
       }
 
@@ -55,13 +51,6 @@ kotlin {
       runTask {
         mainOutputFileName.set("web-app.js")
       }
-      // Browser-Tests komplett deaktivieren (Configuration Cache kompatibel)
-      testTask {
-        useKarma {
-          useChromeHeadless()
-          environment("CHROME_BIN", "/usr/bin/google-chrome-stable")
-        }
-      }
     }
     binaries.executable()
   }
@@ -69,7 +58,6 @@ kotlin {
   sourceSets {
     commonMain.dependencies {
       // Shared modules
-      // implementation(projects.frontend.shared) // REMOVED: Shared module deleted
       implementation(projects.frontend.core.domain)
       implementation(projects.frontend.core.designSystem)
       implementation(projects.frontend.core.navigation)
@@ -92,7 +80,7 @@ kotlin {
       implementation(compose.components.resources)
       implementation(compose.materialIconsExtended)
 
-      // Bundles (Cleaned up dependencies)
+      // Bundles
       implementation(libs.bundles.kmp.common)        // Coroutines, Serialization, DateTime
       implementation(libs.bundles.compose.common)     // ViewModel & Lifecycle
     }
@@ -106,7 +94,7 @@ kotlin {
     jsMain.dependencies {
       implementation(compose.html.core)
       // Benötigt für custom webpack config (wasm.js)
-      implementation(devNpm("copy-webpack-plugin", "11.0.0"))
+      implementation(devNpm("copy-webpack-plugin", libs.versions.copyWebpackPlugin.get()))
     }
 
     commonTest.dependencies {
@@ -115,25 +103,7 @@ kotlin {
   }
 }
 
-// KMP Compile-Optionen
-tasks.withType<org.jetbrains.kotlin.gradle.tasks.KotlinCompile> {
-  compilerOptions {
-    jvmTarget.set(JvmTarget.JVM_25)
-    freeCompilerArgs.addAll(
-      "-opt-in=kotlin.RequiresOptIn",
-      "-Xskip-metadata-version-check", // Für bleeding-edge Versionen
-      // Suppress beta warning for expect/actual declarations used in this module
-      "-Xexpect-actual-classes"
-    )
-  }
-}
-
-// ---------------------------------------------------------------------------
-// Kotlin/JS source maps
-// ---------------------------------------------------------------------------
-// Production source maps must remain enabled for browser debugging.
-
-// Configure a duplicate handling strategy for distribution tasks
+// Duplicate-Handling für Distribution (Zentralisiert in Root build.gradle.kts, aber hier spezifisch für Distribution Tasks)
 tasks.withType<Tar> {
   duplicatesStrategy = DuplicatesStrategy.EXCLUDE
 }
@@ -142,15 +112,6 @@ tasks.withType<Zip> {
   duplicatesStrategy = DuplicatesStrategy.EXCLUDE
 }
 
-// Duplicate-Handling für Distribution
-tasks.withType<Copy> {
-  duplicatesStrategy = DuplicatesStrategy.EXCLUDE
-}
-
-tasks.withType<Sync> {
-  duplicatesStrategy = DuplicatesStrategy.EXCLUDE
-}
-
 // Desktop Application Configuration
 compose.desktop {
   application {