feat(mail-service): initialize Mail-Service and integrate online nomination workflow

- Created `MailServiceApplication` with Spring Boot setup.
- Added `MailPollingService` for IMAP polling, `TurnierNr` extraction, and auto-reply functionality.
- Implemented structured email sending for online nominations via `OnlineNennungFormular`.
- Updated frontend with `Erfolgsscreen` for nomination confirmation and fallback handling.
- Added build configurations for Mail-Service and frontend nomination module.
- Documented phase-based roadmap for Online-Nennung and Mail-Service rollout.

frontend/shells/meldestelle-web/src/wasmJsMain/kotlin/at/mocode/web/WebMainScreen.kt

@@ -15,6 +15,8 @@ import androidx.compose.ui.text.font.FontWeight
 import androidx.compose.ui.unit.dp
 import at.mocode.frontend.core.designsystem.theme.AppColors
 import at.mocode.frontend.features.billing.presentation.BillingViewModel
+import at.mocode.frontend.features.nennung.presentation.web.NennungPayload
+import at.mocode.frontend.features.nennung.presentation.web.OnlineNennungFormular
 import org.koin.compose.viewmodel.koinViewModel
 
 @OptIn(ExperimentalMaterial3Api::class)
@@ -44,10 +46,17 @@ fun WebMainScreen() {
                         currentScreen = WebScreen.Nennung(vId, tId)
                     }
                 )
-                is WebScreen.Nennung -> NennungWebFormular(
-                    veranstaltungId = screen.veranstaltungId,
-                    turnierId = screen.turnierId,
-                    billingViewModel = billingViewModel,
+                is WebScreen.Nennung -> OnlineNennungFormular(
+                    turnierNr = screen.turnierId.toString(),
+                    onNennenAbgeschickt = { payload ->
+                        // Hier wird später der Mail-Versand oder API-Call integriert
+                        println("Nennung abgeschickt: $payload")
+                        currentScreen = WebScreen.Erfolg(payload.email)
+                    },
+                    onBack = { currentScreen = WebScreen.Landing }
+                )
+                is WebScreen.Erfolg -> Erfolgsscreen(
+                    email = screen.email,
                     onBack = { currentScreen = WebScreen.Landing }
                 )
             }
@@ -58,6 +67,27 @@ fun WebMainScreen() {
 sealed class WebScreen {
     data object Landing : WebScreen()
     data class Nennung(val veranstaltungId: Long, val turnierId: Long) : WebScreen()
+    data class Erfolg(val email: String) : WebScreen()
+}
+
+@Composable
+fun Erfolgsscreen(email: String, onBack: () -> Unit) {
+    Box(modifier = Modifier.fillMaxSize().padding(16.dp), contentAlignment = Alignment.Center) {
+        Card(
+            colors = CardDefaults.cardColors(containerColor = AppColors.PrimaryContainer),
+            modifier = Modifier.fillMaxWidth().padding(16.dp)
+        ) {
+            Column(modifier = Modifier.padding(24.dp), horizontalAlignment = Alignment.CenterHorizontally) {
+                Text("Nennung erfolgreich eingegangen!", style = MaterialTheme.typography.headlineSmall, fontWeight = FontWeight.Bold)
+                Spacer(Modifier.height(16.dp))
+                Text("Eine Bestätigungsmail wurde an $email gesendet.", style = MaterialTheme.typography.bodyLarge)
+                Spacer(Modifier.height(24.dp))
+                Button(onClick = onBack) {
+                    Text("Zurück zur Startseite")
+                }
+            }
+        }
+    }
 }
 
 @Composable