chore(turnier-feature): remove unused ViewModels and UI components

- Removed `AbteilungViewModel`, `BewerbAnlegenViewModel`, `BewerbViewModel`, and `CreateBewerbWizardScreen`.
- Cleaned up related imports and unused domain models.

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

@@ -13,6 +13,10 @@ version = "1.0.0"
 
 kotlin {
   jvm()
+  @OptIn(org.jetbrains.kotlin.gradle.ExperimentalWasmDsl::class)
+  wasmJs {
+    browser()
+  }
 
   sourceSets {
     commonMain.dependencies {

frontend/features/billing-feature/src/commonMain/kotlin/at/mocode/frontend/features/billing/data/FakeBillingRepository.kt

@@ -0,0 +1,60 @@
+package at.mocode.frontend.features.billing.data
+
+import at.mocode.frontend.features.billing.domain.BillingRepository
+import at.mocode.frontend.features.billing.domain.BuchungDto
+import at.mocode.frontend.features.billing.domain.BuchungRequest
+import at.mocode.frontend.features.billing.domain.TeilnehmerKontoDto
+
+class FakeBillingRepository : BillingRepository {
+    private val konten = mutableListOf<TeilnehmerKontoDto>()
+    private val buchungen = mutableMapOf<String, MutableList<BuchungDto>>()
+
+    override suspend fun getOrCreateKonto(
+        veranstaltungId: String,
+        personId: String,
+        personName: String
+    ): Result<TeilnehmerKontoDto> {
+        val existing = konten.find { it.personId == personId && it.veranstaltungId == veranstaltungId }
+        if (existing != null) return Result.success(existing)
+
+        val newKonto = TeilnehmerKontoDto(
+            id = "k_${konten.size + 1}",
+            veranstaltungId = veranstaltungId,
+            personId = personId,
+            personName = personName,
+            saldoCent = 0,
+            bemerkungen = null
+        )
+        konten.add(newKonto)
+        buchungen[newKonto.id] = mutableListOf()
+        return Result.success(newKonto)
+    }
+
+    override suspend fun getKonten(veranstaltungId: String): Result<List<TeilnehmerKontoDto>> {
+        return Result.success(konten.filter { it.veranstaltungId == veranstaltungId })
+    }
+
+    override suspend fun getBuchungen(kontoId: String): Result<List<BuchungDto>> {
+        return Result.success(buchungen[kontoId] ?: emptyList())
+    }
+
+    override suspend fun addBuchung(kontoId: String, request: BuchungRequest): Result<TeilnehmerKontoDto> {
+        val index = konten.indexOfFirst { it.id == kontoId }
+        if (index == -1) return Result.failure(Exception("Konto nicht gefunden"))
+
+        val konto = konten[index]
+        val newBuchung = BuchungDto(
+            id = "b_${(buchungen[kontoId]?.size ?: 0) + 1}",
+            kontoId = kontoId,
+            betragCent = request.betragCent,
+            verwendungszweck = request.verwendungszweck,
+            typ = request.typ,
+            gebuchtAm = "2026-04-13T14:30:00Z" // Statischer Zeitstempel für Offline-Betrieb
+        )
+        buchungen.getOrPut(kontoId) { mutableListOf() }.add(newBuchung)
+
+        val updatedKonto = konto.copy(saldoCent = konto.saldoCent + request.betragCent)
+        konten[index] = updatedKonto
+        return Result.success(updatedKonto)
+    }
+}

frontend/features/billing-feature/src/commonMain/kotlin/at/mocode/frontend/features/billing/di/BillingModule.kt

@@ -1,6 +1,6 @@
 package at.mocode.frontend.features.billing.di
 
-import at.mocode.frontend.features.billing.data.DefaultBillingRepository
+import at.mocode.frontend.features.billing.data.FakeBillingRepository
 import at.mocode.frontend.features.billing.domain.BillingCalculator
 import at.mocode.frontend.features.billing.domain.BillingRepository
 import at.mocode.frontend.features.billing.presentation.BillingViewModel
@@ -8,6 +8,7 @@ import org.koin.dsl.module
 
 val billingModule = module {
   single { BillingCalculator() }
-  single<BillingRepository> { DefaultBillingRepository(get()) }
+  // Wir nutzen das Fake-Repository als Fallback für den Desktop/Startup-Mode
+  single<BillingRepository> { FakeBillingRepository() }
   factory { BillingViewModel(get()) }
 }

frontend/features/billing-feature/src/commonMain/kotlin/at/mocode/frontend/features/billing/domain/BillingModels.kt

@@ -18,7 +18,8 @@ value class Money(val cents: Long) {
     val absCents = if (negative) -cents else cents
     val euros = absCents / 100
     val rest = absCents % 100
-    return "%s%d,%02d €".format(if (negative) "-" else "", euros, rest)
+    val restStr = if (rest < 10) "0$rest" else "$rest"
+    return "${if (negative) "-" else ""}$euros,$restStr €"
   }
 }
 

frontend/features/billing-feature/src/commonMain/kotlin/at/mocode/frontend/features/billing/presentation/BillingViewModel.kt

@@ -28,40 +28,56 @@ class BillingViewModel(
 
   fun loadKonten(veranstaltungId: String) {
     viewModelScope.launch {
-      _uiState.value = _uiState.value.copy(isLoading = true)
-      repository.getKonten(veranstaltungId)
-        .onSuccess { konten ->
-          _uiState.value = _uiState.value.copy(konten = konten, isLoading = false, error = null)
-        }
-        .onFailure {
-          _uiState.value = _uiState.value.copy(isLoading = false, error = it.message)
-        }
+      _uiState.value = _uiState.value.copy(isLoading = true, error = null)
+      try {
+        repository.getKonten(veranstaltungId)
+          .onSuccess { konten ->
+            _uiState.value = _uiState.value.copy(konten = konten, isLoading = false, error = null)
+          }
+          .onFailure {
+            _uiState.value = _uiState.value.copy(
+              isLoading = false,
+              error = "Fehler beim Laden der Konten: ${it.message ?: "Unbekannter Fehler"}"
+            )
+          }
+      } catch (e: Exception) {
+        _uiState.value = _uiState.value.copy(
+          isLoading = false,
+          error = "Kritischer Netzwerkfehler: ${e.message}"
+        )
+      }
     }
   }
 
   fun loadKonto(veranstaltungId: String, personId: String, personName: String) {
     viewModelScope.launch {
-      _uiState.value = _uiState.value.copy(isLoading = true)
+      _uiState.value = _uiState.value.copy(isLoading = true, error = null)
       repository.getOrCreateKonto(veranstaltungId, personId, personName)
         .onSuccess { konto ->
           _uiState.value = _uiState.value.copy(selectedKonto = konto, error = null)
           loadBuchungen(konto.id)
         }
         .onFailure {
-          _uiState.value = _uiState.value.copy(isLoading = false, error = it.message)
+          _uiState.value = _uiState.value.copy(
+            isLoading = false,
+            error = "Fehler beim Laden/Erstellen des Kontos: ${it.message ?: "Unbekannter Fehler"}"
+          )
         }
     }
   }
 
   private fun loadBuchungen(kontoId: String) {
     viewModelScope.launch {
-      _uiState.value = _uiState.value.copy(isLoading = true)
+      _uiState.value = _uiState.value.copy(isLoading = true, error = null)
       repository.getBuchungen(kontoId)
         .onSuccess { buchungen ->
           _uiState.value = _uiState.value.copy(buchungen = buchungen, isLoading = false, error = null)
         }
         .onFailure {
-          _uiState.value = _uiState.value.copy(isLoading = false, error = it.message)
+          _uiState.value = _uiState.value.copy(
+            isLoading = false,
+            error = "Fehler beim Laden der Buchungen: ${it.message ?: "Unbekannter Fehler"}"
+          )
         }
     }
   }
@@ -69,15 +85,18 @@ class BillingViewModel(
   fun buche(betragCent: Long, zweck: String, typ: String) {
     val konto = _uiState.value.selectedKonto ?: return
     viewModelScope.launch {
-      _uiState.value = _uiState.value.copy(isLoading = true)
+      _uiState.value = _uiState.value.copy(isLoading = true, error = null)
       val request = BuchungRequest(betragCent = betragCent, verwendungszweck = zweck, typ = typ)
       repository.addBuchung(konto.id, request)
         .onSuccess { aktualisiertesKonto ->
-          _uiState.value = _uiState.value.copy(selectedKonto = aktualisiertesKonto)
+          _uiState.value = _uiState.value.copy(selectedKonto = aktualisiertesKonto, error = null)
           loadBuchungen(konto.id)
         }
         .onFailure {
-          _uiState.value = _uiState.value.copy(isLoading = false, error = it.message)
+          _uiState.value = _uiState.value.copy(
+            isLoading = false,
+            error = "Fehler beim Buchen: ${it.message ?: "Unbekannter Fehler"}"
+          )
         }
     }
   }