feat(lockdown): Lock Now auto-disconnect, session status, provision confirm

- T027/T028: Auto-disconnect on LockNowAcknowledged state in app shell
- T020/T021: Confirm passphrase field in provision mode with mismatch validation
- T035/T036: LockdownSessionStatus composable showing boots remaining and expiry
- Wire session status and Lock Now button enabled state based on sessionAuthorized
- Expose lockdownTokenInfo and sessionAuthorized from RadioConfigViewModel

app/src/main/kotlin/org/meshtastic/app/ui/Main.kt

@@ -32,6 +32,7 @@ import co.touchlab.kermit.Logger
 import org.koin.compose.viewmodel.koinViewModel
 import org.meshtastic.app.BuildConfig
 import org.meshtastic.core.model.ConnectionState
+import org.meshtastic.core.model.service.LockdownState
 import org.meshtastic.core.navigation.NodesRoute
 import org.meshtastic.core.navigation.TopLevelDestination
 import org.meshtastic.core.navigation.rememberMultiBackstack
@@ -76,6 +77,12 @@ fun MainScreen() {
         },
         onDisconnect = { viewModel.setDeviceAddress("n") },
     )
+    // Auto-disconnect when firmware acknowledges Lock Now
+    LaunchedEffect(lockdownState) {
+        if (lockdownState is LockdownState.LockNowAcknowledged) {
+            viewModel.setDeviceAddress("n")
+        }
+    }
 
     MeshtasticAppShell(multiBackstack = multiBackstack, uiViewModel = viewModel, hostModifier = Modifier) {
         MeshtasticNavigationSuite(

feature/settings/src/commonMain/kotlin/org/meshtastic/feature/settings/lockdown/LockdownDialog.kt

@@ -74,6 +74,7 @@ fun LockdownDialog(
     if (!shouldShow) return
 
     var passphrase by rememberSaveable { mutableStateOf("") }
+    var confirmPassphrase by rememberSaveable { mutableStateOf("") }
     var passwordVisible by rememberSaveable { mutableStateOf(false) }
     var boots by rememberSaveable { mutableIntStateOf(DEFAULT_BOOTS) }
     var hours by rememberSaveable { mutableIntStateOf(0) }
@@ -81,7 +82,9 @@ fun LockdownDialog(
     val isProvisioning = lockdownState is LockdownState.NeedsProvision
     val title = if (isProvisioning) "Set Passphrase" else "Enter Passphrase"
     val inBackoff = lockdownState is LockdownState.UnlockBackoff
-    val isValid = passphrase.isNotEmpty() && passphrase.length <= MAX_PASSPHRASE_LEN && !inBackoff
+    val passphraseValid = passphrase.isNotEmpty() && passphrase.length <= MAX_PASSPHRASE_LEN
+    val confirmValid = !isProvisioning || passphrase == confirmPassphrase
+    val isValid = passphraseValid && confirmValid && !inBackoff
 
     AlertDialog(
         onDismissRequest = {}, // Non-dismissable
@@ -138,6 +141,21 @@ fun LockdownDialog(
                 )
 
                 if (isProvisioning) {
+                    Spacer(modifier = Modifier.height(SPACING_DP.dp))
+                    OutlinedTextField(
+                        value = confirmPassphrase,
+                        onValueChange = { if (it.length <= MAX_PASSPHRASE_LEN) confirmPassphrase = it },
+                        label = { Text("Confirm passphrase") },
+                        singleLine = true,
+                        visualTransformation = PasswordVisualTransformation(),
+                        isError = confirmPassphrase.isNotEmpty() && passphrase != confirmPassphrase,
+                        supportingText = if (confirmPassphrase.isNotEmpty() && passphrase != confirmPassphrase) {
+                            { Text("Passphrases do not match") }
+                        } else {
+                            null
+                        },
+                        modifier = Modifier.fillMaxWidth(),
+                    )
                     Spacer(modifier = Modifier.height(SPACING_DP.dp))
                     Row(
                         modifier = Modifier.fillMaxWidth(),

feature/settings/src/commonMain/kotlin/org/meshtastic/feature/settings/lockdown/LockdownSessionStatus.kt

@@ -0,0 +1,62 @@
+/*
+ * Copyright (c) 2025-2026 Meshtastic LLC
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+package org.meshtastic.feature.settings.lockdown
+
+import androidx.compose.foundation.layout.Column
+import androidx.compose.foundation.layout.padding
+import androidx.compose.material3.MaterialTheme
+import androidx.compose.material3.Text
+import androidx.compose.runtime.Composable
+import androidx.compose.ui.Modifier
+import androidx.compose.ui.unit.dp
+import org.meshtastic.core.model.service.LockdownTokenInfo
+
+/**
+ * Displays lockdown session token status: remaining boots and expiry information.
+ * Visible only when the session is unlocked and token info is available.
+ */
+@Composable
+fun LockdownSessionStatus(
+    tokenInfo: LockdownTokenInfo?,
+    modifier: Modifier = Modifier,
+) {
+    if (tokenInfo == null) return
+
+    Column(modifier = modifier.padding(horizontal = PADDING_DP.dp, vertical = PADDING_VERTICAL_DP.dp)) {
+        Text(
+            text = "Session: ${tokenInfo.bootsRemaining} reboots remaining",
+            style = MaterialTheme.typography.bodySmall,
+            color = MaterialTheme.colorScheme.onSurfaceVariant,
+        )
+        if (tokenInfo.expiryEpoch > 0L) {
+            Text(
+                text = "Expires at epoch ${tokenInfo.expiryEpoch}",
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        } else {
+            Text(
+                text = "No time limit",
+                style = MaterialTheme.typography.bodySmall,
+                color = MaterialTheme.colorScheme.onSurfaceVariant,
+            )
+        }
+    }
+}
+
+private const val PADDING_DP = 8
+private const val PADDING_VERTICAL_DP = 4

feature/settings/src/commonMain/kotlin/org/meshtastic/feature/settings/radio/RadioConfigViewModel.kt

@@ -140,6 +140,9 @@ open class RadioConfigViewModel(
     private val lockdownCoordinator: LockdownCoordinator,
 ) : ViewModel() {
 
+    val lockdownTokenInfo = serviceRepository.lockdownTokenInfo
+    val sessionAuthorized = serviceRepository.sessionAuthorized
+
     fun sendLockNow() {
         viewModelScope.launch { lockdownCoordinator.lockNow() }
     }

feature/settings/src/commonMain/kotlin/org/meshtastic/feature/settings/radio/component/SecurityConfigScreen.kt

@@ -63,6 +63,7 @@ import org.meshtastic.core.ui.component.SwitchPreference
 import org.meshtastic.core.ui.component.TitledCard
 import org.meshtastic.core.ui.icon.MeshtasticIcons
 import org.meshtastic.core.ui.icon.Warning
+import org.meshtastic.feature.settings.lockdown.LockdownSessionStatus
 import org.meshtastic.feature.settings.radio.RadioConfigViewModel
 import org.meshtastic.proto.Config
 import kotlin.random.Random
@@ -214,10 +215,15 @@ fun SecurityConfigScreenCommon(viewModel: RadioConfigViewModel, onBack: () -> Un
                 )
                 HorizontalDivider()
                 // TODO(lockdown): Re-implement Lock Now button with KMP-compatible UI (Phase 5, T025-T026)
+                val tokenInfo by viewModel.lockdownTokenInfo.collectAsStateWithLifecycle()
+                val authorized by viewModel.sessionAuthorized.collectAsStateWithLifecycle()
+                if (authorized) {
+                    LockdownSessionStatus(tokenInfo = tokenInfo)
+                }
                 NodeActionButton(
                     modifier = Modifier.padding(horizontal = 8.dp),
                     title = "Lock Now",
-                    enabled = state.connected,
+                    enabled = state.connected && authorized,
                     onClick = { viewModel.sendLockNow() },
                 )
             }