chore(MP-23): network DI client, frontend architecture guards, detekt & ktlint setup, docs, ping DI factory (#21)

* chore(MP-21): snapshot pre-refactor state (Epic 1)

* chore(MP-22): scaffold new repo structure, relocate Docker Compose, move frontend/backend modules, update Makefile; add docs mapping and env template

* MP-22 Epic 2: Erfolgreich umgesetzt und verifiziert

* MP-23 Epic 3: Gradle/Build Governance zentralisieren

frontend/shells/meldestelle-portal/src/jvmMain/kotlin/DevelopmentMode.jvm.kt

@@ -0,0 +1,2 @@
+actual fun isDevelopmentMode(): Boolean =
+  System.getProperty("development.mode", "false").toBoolean()

frontend/shells/meldestelle-portal/src/jvmMain/kotlin/main.kt

@@ -0,0 +1,23 @@
+import androidx.compose.ui.window.Window
+import androidx.compose.ui.window.application
+import androidx.compose.ui.window.WindowState
+import androidx.compose.ui.unit.dp
+import at.mocode.clients.shared.di.initKoin
+import at.mocode.frontend.core.network.networkModule
+
+fun main() = application {
+  // Initialize DI (Koin) with shared modules + network module
+  try {
+    initKoin { modules(networkModule) }
+    println("[DesktopApp] Koin initialized with networkModule")
+  } catch (e: Exception) {
+    println("[DesktopApp] Koin initialization warning: ${e.message}")
+  }
+  Window(
+    onCloseRequest = ::exitApplication,
+    title = "Meldestelle - Desktop Development",
+    state = WindowState(width = 1200.dp, height = 800.dp)
+  ) {
+    MainApp()
+  }
+}