feat: Add biometric authentication toggle in ProfileScreen with state management

app/src/main/java/com/rosetta/messenger/ui/settings/ProfileScreen.kt

@@ -43,7 +43,12 @@ import androidx.compose.ui.unit.Dp
 import androidx.compose.ui.unit.IntOffset
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
+import androidx.fragment.app.FragmentActivity
+import com.rosetta.messenger.biometric.BiometricAuthManager
+import com.rosetta.messenger.biometric.BiometricAvailability
+import com.rosetta.messenger.biometric.BiometricPreferences
 import kotlinx.coroutines.delay
+import kotlinx.coroutines.flow.first
 import kotlinx.coroutines.launch
 import kotlin.math.roundToInt
 
@@ -132,6 +137,21 @@ fun ProfileScreen(
     onNavigateToLogs: () -> Unit = {},
     viewModel: ProfileViewModel = androidx.lifecycle.viewmodel.compose.viewModel()
 ) {
+    val context = LocalContext.current
+    val activity = context as? FragmentActivity
+    val biometricManager = remember { BiometricAuthManager(context) }
+    val biometricPrefs = remember { BiometricPreferences(context) }
+    val scope = rememberCoroutineScope()
+    
+    // Biometric state
+    var biometricAvailable by remember { mutableStateOf<BiometricAvailability>(BiometricAvailability.NotAvailable("Checking...")) }
+    var isBiometricEnabled by remember { mutableStateOf(false) }
+    
+    // Check biometric availability
+    LaunchedEffect(Unit) {
+        biometricAvailable = biometricManager.isBiometricAvailable()
+        isBiometricEnabled = biometricPrefs.isBiometricEnabled.first()
+    }
     // Цвета в зависимости от темы
     val backgroundColor = if (isDarkTheme) Color(0xFF1A1A1A) else Color(0xFFFFFFFF)
     val surfaceColor = if (isDarkTheme) Color(0xFF2C2C2E) else Color(0xFFF2F2F7)
@@ -194,9 +214,6 @@ fun ProfileScreen(
         }
     }
     
-    // Context
-    val context = LocalContext.current
-    
     // Show success toast and update local profile
     LaunchedEffect(profileState.saveSuccess) {
         if (profileState.saveSuccess) {
@@ -305,8 +322,41 @@ fun ProfileScreen(
                     icon = Icons.Outlined.Lock,
                     title = "Safety",
                     onClick = onNavigateToSafety,
-                    isDarkTheme = isDarkTheme
+                    isDarkTheme = isDarkTheme,
+                    showDivider = biometricAvailable is BiometricAvailability.Available
                 )
+                
+                // Biometric toggle (only show if available)
+                if (biometricAvailable is BiometricAvailability.Available && activity != null) {
+                    TelegramBiometricItem(
+                        isEnabled = isBiometricEnabled,
+                        onToggle = {
+                            scope.launch {
+                                if (isBiometricEnabled) {
+                                    // Disable biometric
+                                    biometricPrefs.disableBiometric()
+                                    biometricPrefs.removeEncryptedPassword(accountPublicKey)
+                                    isBiometricEnabled = false
+                                    android.widget.Toast.makeText(
+                                        context,
+                                        "Biometric authentication disabled",
+                                        android.widget.Toast.LENGTH_SHORT
+                                    ).show()
+                                } else {
+                                    // Enable biometric
+                                    biometricPrefs.enableBiometric()
+                                    isBiometricEnabled = true
+                                    android.widget.Toast.makeText(
+                                        context,
+                                        "Biometric authentication enabled. Your password will be securely saved on next unlock.",
+                                        android.widget.Toast.LENGTH_LONG
+                                    ).show()
+                                }
+                            }
+                        },
+                        isDarkTheme = isDarkTheme
+                    )
+                }
 
                 Spacer(modifier = Modifier.height(24.dp))
 
@@ -831,6 +881,52 @@ private fun TelegramSettingsItem(
     }
 }
 
+@Composable
+private fun TelegramBiometricItem(
+    isEnabled: Boolean,
+    onToggle: () -> Unit,
+    isDarkTheme: Boolean
+) {
+    val textColor = if (isDarkTheme) Color.White else Color.Black
+    val iconColor = if (isDarkTheme) Color(0xFF8E8E93) else Color(0xFF666666)
+    val primaryBlue = Color(0xFF007AFF)
+
+    Row(
+        modifier = Modifier
+            .fillMaxWidth()
+            .clickable(onClick = onToggle)
+            .padding(horizontal = 16.dp, vertical = 14.dp),
+        verticalAlignment = Alignment.CenterVertically
+    ) {
+        Icon(
+            imageVector = Icons.Outlined.Fingerprint,
+            contentDescription = null,
+            tint = iconColor,
+            modifier = Modifier.size(24.dp)
+        )
+
+        Spacer(modifier = Modifier.width(20.dp))
+
+        Text(
+            text = "Biometric Authentication",
+            fontSize = 16.sp,
+            color = textColor,
+            modifier = Modifier.weight(1f)
+        )
+        
+        Switch(
+            checked = isEnabled,
+            onCheckedChange = { onToggle() },
+            colors = SwitchDefaults.colors(
+                checkedThumbColor = Color.White,
+                checkedTrackColor = primaryBlue,
+                uncheckedThumbColor = Color.White,
+                uncheckedTrackColor = if (isDarkTheme) Color(0xFF3A3A3A) else Color(0xFFE0E0E0)
+            )
+        )
+    }
+}
+
 @Composable
 private fun TelegramLogoutItem(
     onClick: () -> Unit,