feat: clone instance with full details for editing

Clone button on site list now navigates to setup screen pre-filled
with the source instance's URL, API key, and site ID. User can edit
all fields and save as a new instance. API key is resolved from
encrypted storage via the ViewModel, never passed through nav args.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

app/src/main/java/no/naiv/implausibly/ui/navigation/AppNavHost.kt

@@ -70,6 +70,22 @@ fun AppNavHost(
             )
         }
 
+        composable(
+            route = Routes.SETUP_CLONE,
+            arguments = listOf(
+                navArgument("cloneInstanceId") { type = NavType.StringType },
+                navArgument("cloneSiteId") { type = NavType.StringType }
+            )
+        ) {
+            SetupScreen(
+                onInstanceAdded = { instanceId ->
+                    navController.navigate(Routes.siteList(instanceId)) {
+                        popUpTo(0) { inclusive = true }
+                    }
+                }
+            )
+        }
+
         composable(
             route = Routes.SITE_LIST,
             arguments = listOf(navArgument("instanceId") { type = NavType.StringType })
@@ -80,6 +96,9 @@ fun AppNavHost(
                         popUpTo(Routes.SETUP) { inclusive = true }
                     }
                 },
+                onCloneSite = { instanceId, siteId ->
+                    navController.navigate(Routes.setupClone(instanceId, siteId))
+                },
                 onBack = { navController.popBackStack() }
             )
         }

app/src/main/java/no/naiv/implausibly/ui/navigation/Routes.kt

@@ -8,9 +8,11 @@ package no.naiv.implausibly.ui.navigation
 object Routes {
     const val LOADING = "loading"
     const val SETUP = "setup"
+    const val SETUP_CLONE = "setup?cloneInstanceId={cloneInstanceId}&cloneSiteId={cloneSiteId}"
     const val SITE_LIST = "site_list/{instanceId}"
     const val DASHBOARD = "dashboard/{instanceId}/{siteId}"
 
     fun siteList(instanceId: String) = "site_list/$instanceId"
     fun dashboard(instanceId: String, siteId: String) = "dashboard/$instanceId/$siteId"
+    fun setupClone(instanceId: String, siteId: String) = "setup?cloneInstanceId=$instanceId&cloneSiteId=$siteId"
 }

app/src/main/java/no/naiv/implausibly/ui/setup/SetupViewModel.kt

@@ -1,6 +1,7 @@
 // SPDX-License-Identifier: GPL-3.0-only
 package no.naiv.implausibly.ui.setup
 
+import androidx.lifecycle.SavedStateHandle
 import androidx.lifecycle.ViewModel
 import androidx.lifecycle.viewModelScope
 import dagger.hilt.android.lifecycle.HiltViewModel
@@ -39,16 +40,39 @@ sealed class TestResult {
 
 @HiltViewModel
 class SetupViewModel @Inject constructor(
+    savedStateHandle: SavedStateHandle,
     private val instanceRepository: InstanceRepository,
     private val siteRepository: SiteRepository,
     private val appPreferences: AppPreferences
 ) : ViewModel() {
 
+    private val cloneInstanceId: String? = savedStateHandle["cloneInstanceId"]
+    private val cloneSiteId: String? = savedStateHandle["cloneSiteId"]
+
     private val _uiState = MutableStateFlow(SetupUiState())
     val uiState: StateFlow<SetupUiState> = _uiState.asStateFlow()
 
     init {
         loadExistingInstances()
+        if (cloneInstanceId != null) {
+            loadCloneData(cloneInstanceId, cloneSiteId)
+        }
+    }
+
+    private fun loadCloneData(instanceId: String, siteId: String?) {
+        viewModelScope.launch {
+            val instance = instanceRepository.getById(instanceId) ?: return@launch
+            val apiKey = instanceRepository.getApiKey(instance) ?: ""
+
+            _uiState.update {
+                it.copy(
+                    baseUrl = instance.baseUrl,
+                    apiKey = apiKey,
+                    name = "",
+                    siteId = siteId ?: ""
+                )
+            }
+        }
     }
 
     private fun loadExistingInstances() {
@@ -95,7 +119,6 @@ class SetupViewModel @Inject constructor(
                     isTesting = false,
                     testResult = if (error == null) TestResult.Success else TestResult.Failure(error),
                     name = if (error == null && it.name.isBlank()) {
-                        // Auto-fill name from site ID if blank
                         state.siteId
                     } else {
                         it.name
@@ -121,10 +144,8 @@ class SetupViewModel @Inject constructor(
                 apiKey = apiKey
             )
 
-            // Also store the site ID
             siteRepository.addSite(state.siteId, instance.id)
 
-            // Set as selected
             appPreferences.setSelectedInstanceId(instance.id)
             appPreferences.setSelectedSiteId(state.siteId)
 

app/src/main/java/no/naiv/implausibly/ui/sites/SiteListScreen.kt

@@ -42,6 +42,7 @@ import androidx.hilt.navigation.compose.hiltViewModel
 @Composable
 fun SiteListScreen(
     onSiteSelected: (instanceId: String, siteId: String) -> Unit,
+    onCloneSite: (instanceId: String, siteId: String) -> Unit = { _, _ -> },
     onBack: () -> Unit,
     viewModel: SiteListViewModel = hiltViewModel()
 ) {
@@ -159,7 +160,7 @@ fun SiteListScreen(
                                     style = MaterialTheme.typography.titleMedium,
                                     modifier = Modifier.weight(1f)
                                 )
-                                IconButton(onClick = { viewModel.cloneSite(site.id) }) {
+                                IconButton(onClick = { onCloneSite(uiState.instanceId, site.id) }) {
                                     Icon(
                                         Icons.Default.ContentCopy,
                                         contentDescription = "Clone site"