feat(onboarding): Explicit Device Enrollment für Master-Geräte hinzugefügt

- Master-Geräte können erwartete Clients inkl. Name & Rolle definieren.
- Neue Rollen (`RICHTER`, `ZEITNEHMER` etc.) integriert.
- Backend- und Frontend-Validierung erweitert, UI-Komponente für Client-Verwaltung.

Signed-off-by: Stefan Mogeritsch <stefan.mo.co@gmail.com>

frontend/shells/meldestelle-desktop/settings.json

@@ -1,6 +1,12 @@
 {
   "geraetName": "Meldestelle",
   "sharedKey": "Meldestelle",
-  "backupPath": "/mocode/Meldestelle/docs/temp",
-  "networkRole": "MASTER"
+  "backupPath": "/home/stefan/WsMeldestelle/Meldestelle/meldestelle/docs/temp",
+  "networkRole": "MASTER",
+  "expectedClients": [
+    {
+      "name": "Richter-Turm",
+      "role": "RICHTER"
+    }
+  ]
 }

frontend/shells/meldestelle-desktop/src/jvmMain/kotlin/at/mocode/desktop/screens/onboarding/OnboardingSettings.kt

@@ -5,15 +5,29 @@ import kotlinx.serialization.Serializable
 @Serializable
 enum class NetworkRole {
   MASTER,
-  CLIENT
+  CLIENT,
+  RICHTER,
+  ZEITNEHMER,
+  STALLMEISTER,
+  ANZEIGE,
+  PARCOURS_CHEF
 }
 
+@Serializable
+data class ExpectedClient(
+  val name: String,
+  val role: NetworkRole,
+  val isOnline: Boolean = false,
+  val isSynchronized: Boolean = true
+)
+
 @Serializable
 data class OnboardingSettings(
   val geraetName: String = "",
   val sharedKey: String = "",
   val backupPath: String = "",
   val networkRole: NetworkRole = NetworkRole.CLIENT,
+  val expectedClients: List<ExpectedClient> = emptyList(),
   val syncInterval: Int = 30, // in Minuten
   val defaultPrinter: String = ""
 )

frontend/shells/meldestelle-desktop/src/jvmMain/kotlin/at/mocode/desktop/screens/onboarding/OnboardingValidator.kt

@@ -37,9 +37,19 @@ object OnboardingValidator {
    * Gibt `true` zurück, wenn alle Pflichtfelder gültig sind und
    * der „Weiter"-Button aktiviert werden darf.
    */
-  fun canContinue(settings: OnboardingSettings): Boolean =
-    isNameValid(settings.geraetName) &&
+  fun canContinue(settings: OnboardingSettings): Boolean {
+    val basicValid = isNameValid(settings.geraetName) &&
       isKeyValid(settings.sharedKey) &&
       isBackupPathValid(settings.backupPath) &&
       isSyncIntervalValid(settings.syncInterval)
+
+    if (!basicValid) return false
+
+    // Falls Master, müssen alle erwarteten Clients einen Namen haben
+    if (settings.networkRole == NetworkRole.MASTER) {
+      return settings.expectedClients.all { it.name.trim().isNotEmpty() }
+    }
+
+    return true
+  }
 }

frontend/shells/meldestelle-desktop/src/jvmMain/kotlin/at/mocode/desktop/v2/Screens.kt

@@ -24,6 +24,7 @@ import androidx.compose.ui.text.input.PasswordVisualTransformation
 import androidx.compose.ui.text.input.VisualTransformation
 import androidx.compose.ui.tooling.preview.Preview
 import androidx.compose.ui.unit.dp
+import at.mocode.desktop.screens.onboarding.ExpectedClient
 import at.mocode.desktop.screens.onboarding.NetworkRole
 import at.mocode.desktop.screens.onboarding.OnboardingSettings
 import at.mocode.desktop.screens.onboarding.OnboardingValidator
@@ -142,6 +143,77 @@ fun OnboardingScreen(
               )
             }
 
+            if (settings.networkRole == NetworkRole.MASTER) {
+              HorizontalDivider(Modifier.padding(vertical = 8.dp))
+              Text("📋 Erwartete Geräte (Clients)", style = MaterialTheme.typography.titleSmall)
+              Text(
+                "Definiere hier, welche Geräte sich in diesem Netzwerk anmelden dürfen.",
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant
+              )
+
+              settings.expectedClients.forEachIndexed { index, client ->
+                Row(
+                  modifier = Modifier.fillMaxWidth().padding(vertical = 4.dp),
+                  verticalAlignment = Alignment.CenterVertically,
+                  horizontalArrangement = Arrangement.spacedBy(8.dp)
+                ) {
+                  MsTextField(
+                    value = client.name,
+                    onValueChange = { newName ->
+                      val newList = settings.expectedClients.toMutableList()
+                      newList[index] = client.copy(name = newName)
+                      onSettingsChange(settings.copy(expectedClients = newList))
+                    },
+                    label = "Name",
+                    modifier = Modifier.weight(1f)
+                  )
+
+                  var expanded by remember { mutableStateOf(false) }
+                  Box {
+                    OutlinedButton(onClick = { expanded = true }) {
+                      Text(client.role.name)
+                      Icon(Icons.Default.ArrowDropDown, null)
+                    }
+                    DropdownMenu(expanded = expanded, onDismissRequest = { expanded = false }) {
+                      NetworkRole.entries.filter { it != NetworkRole.MASTER }.forEach { role ->
+                        DropdownMenuItem(
+                          text = { Text(role.name) },
+                          onClick = {
+                            val newList = settings.expectedClients.toMutableList()
+                            newList[index] = client.copy(role = role)
+                            onSettingsChange(settings.copy(expectedClients = newList))
+                            expanded = false
+                          }
+                        )
+                      }
+                    }
+                  }
+
+                  IconButton(onClick = {
+                    val newList = settings.expectedClients.toMutableList()
+                    newList.removeAt(index)
+                    onSettingsChange(settings.copy(expectedClients = newList))
+                  }) {
+                    Icon(Icons.Default.Delete, contentDescription = "Entfernen", tint = MaterialTheme.colorScheme.error)
+                  }
+                }
+              }
+
+              TextButton(
+                onClick = {
+                  val newList = settings.expectedClients.toMutableList()
+                  newList.add(ExpectedClient("Neues Gerät", NetworkRole.CLIENT))
+                  onSettingsChange(settings.copy(expectedClients = newList))
+                },
+                modifier = Modifier.padding(top = 8.dp)
+              ) {
+                Icon(Icons.Default.Add, null)
+                Spacer(Modifier.width(8.dp))
+                Text("Gerät hinzufügen")
+              }
+            }
+
             var showPrinterDialog by remember { mutableStateOf(false) }
             val availablePrinters = remember {
               PrintServiceLookup.lookupPrintServices(null, null).map { it.name }

frontend/shells/meldestelle-desktop/src/jvmTest/kotlin/at/mocode/desktop/screens/onboarding/OnboardingValidatorTest.kt

@@ -136,7 +136,7 @@ class OnboardingValidatorTest {
 
   @Test
   fun `B2 canContinue bleibt stabil bei wiederholtem Aufruf mit gleichen Werten`() {
-    // Simuliert schnelles Doppelklick: canContinue darf sich nicht ändern
+    // Simuliert schneller Doppelklick: canContinue darf sich nicht ändern
     val settings = OnboardingSettings(geraetName = "Meldestelle", sharedKey = "Neumarkt2026", backupPath = "/tmp")
     val first = OnboardingValidator.canContinue(settings)
     val second = OnboardingValidator.canContinue(settings)
@@ -186,4 +186,36 @@ class OnboardingValidatorTest {
       "Nach Abbrechen darf der Weiter-Button nicht aktiviert sein"
     )
   }
+
+  // ─── Explicit Device Enrollment (Master) ───────────────────────────────────
+
+  @Test
+  fun `Master canContinue false wenn ein erwarteter Client keinen Namen hat`() {
+    val masterSettings = OnboardingSettings(
+      geraetName = "Master-PC",
+      sharedKey = "Neumarkt2026",
+      backupPath = "/tmp",
+      networkRole = NetworkRole.MASTER,
+      expectedClients = listOf(
+        ExpectedClient("Richter 1", NetworkRole.RICHTER),
+        ExpectedClient("", NetworkRole.ZEITNEHMER) // Ungültig: Name leer
+      )
+    )
+    assertFalse(OnboardingValidator.canContinue(masterSettings))
+  }
+
+  @Test
+  fun `Master canContinue true wenn alle erwarteten Clients Namen haben`() {
+    val masterSettings = OnboardingSettings(
+      geraetName = "Master-PC",
+      sharedKey = "Neumarkt2026",
+      backupPath = "/tmp",
+      networkRole = NetworkRole.MASTER,
+      expectedClients = listOf(
+        ExpectedClient("Richter 1", NetworkRole.RICHTER),
+        ExpectedClient("Zeitnehmer 1", NetworkRole.ZEITNEHMER)
+      )
+    )
+    assertTrue(OnboardingValidator.canContinue(masterSettings))
+  }
 }