fix: per-app proxy - исправлен формат чтения списка приложений из SharedPreferences

- Удалён устаревший формат с Base64 + ObjectInputStream
- Теперь используется стандартный getStringSet() для чтения List<String>
- Совместимо с Flutter SharedPreferences plugin
- Убраны неиспользуемые импорты (Base64, ByteArrayInputStream, ObjectInputStream)

android/app/src/main/kotlin/com/umbrix/app/Settings.kt

@@ -0,0 +1,115 @@
+package com.umbrix.app
+
+import android.content.Context
+import com.umbrix.app.bg.ProxyService
+import com.umbrix.app.bg.VPNService
+import com.umbrix.app.constant.PerAppProxyMode
+import com.umbrix.app.constant.ServiceMode
+import com.umbrix.app.constant.SettingsKey
+import org.json.JSONObject
+import java.io.File
+
+object Settings {
+
+    private val preferences by lazy {
+        val context = Application.application.applicationContext
+        context.getSharedPreferences("FlutterSharedPreferences", Context.MODE_PRIVATE)
+    }
+
+    var perAppProxyMode: String
+        get() = preferences.getString(SettingsKey.PER_APP_PROXY_MODE, PerAppProxyMode.OFF)!!
+        set(value) = preferences.edit().putString(SettingsKey.PER_APP_PROXY_MODE, value).apply()
+
+    val perAppProxyEnabled: Boolean
+        get() = perAppProxyMode != PerAppProxyMode.OFF
+
+    val perAppProxyList: List<String>
+        get() {
+            val key = if (perAppProxyMode == PerAppProxyMode.INCLUDE) {
+                SettingsKey.PER_APP_PROXY_INCLUDE_LIST
+            } else {
+                SettingsKey.PER_APP_PROXY_EXCLUDE_LIST
+            }
+            // Flutter SharedPreferences plugin сохраняет List<String> как StringSet
+            // Читаем напрямую без дополнительной сериализации
+            return preferences.getStringSet(key, emptySet())?.toList() ?: emptyList()
+        }
+
+    var activeConfigPath: String
+        get() = preferences.getString(SettingsKey.ACTIVE_CONFIG_PATH, "")!!
+        set(value) = preferences.edit().putString(SettingsKey.ACTIVE_CONFIG_PATH, value).apply()
+
+    var activeProfileName: String
+        get() = preferences.getString(SettingsKey.ACTIVE_PROFILE_NAME, "")!!
+        set(value) = preferences.edit().putString(SettingsKey.ACTIVE_PROFILE_NAME, value).apply()
+
+    var serviceMode: String
+        get() = preferences.getString(SettingsKey.SERVICE_MODE, ServiceMode.VPN)!!
+        set(value) = preferences.edit().putString(SettingsKey.SERVICE_MODE, value).apply()
+
+    var configOptions: String
+        get() = preferences.getString(SettingsKey.CONFIG_OPTIONS, "")!!
+        set(value) = preferences.edit().putString(SettingsKey.CONFIG_OPTIONS, value).apply()
+
+    var debugMode: Boolean
+        get() = preferences.getBoolean(SettingsKey.DEBUG_MODE, false)
+        set(value) = preferences.edit().putBoolean(SettingsKey.DEBUG_MODE, value).apply()
+
+    var disableMemoryLimit: Boolean
+        get() = preferences.getBoolean(SettingsKey.DISABLE_MEMORY_LIMIT, false)
+        set(value) =
+            preferences.edit().putBoolean(SettingsKey.DISABLE_MEMORY_LIMIT, value).apply()
+
+    var dynamicNotification: Boolean
+        get() = preferences.getBoolean(SettingsKey.DYNAMIC_NOTIFICATION, true)
+        set(value) =
+            preferences.edit().putBoolean(SettingsKey.DYNAMIC_NOTIFICATION, value).apply()
+
+    var systemProxyEnabled: Boolean
+        get() = preferences.getBoolean(SettingsKey.SYSTEM_PROXY_ENABLED, true)
+        set(value) =
+            preferences.edit().putBoolean(SettingsKey.SYSTEM_PROXY_ENABLED, value).apply()
+
+    var startedByUser: Boolean
+        get() = preferences.getBoolean(SettingsKey.STARTED_BY_USER, false)
+        set(value) = preferences.edit().putBoolean(SettingsKey.STARTED_BY_USER, value).apply()
+
+    fun serviceClass(): Class<*> {
+        return when (serviceMode) {
+            ServiceMode.VPN -> VPNService::class.java
+            else -> ProxyService::class.java
+        }
+    }
+
+    private var currentServiceMode : String? = null
+
+    suspend fun rebuildServiceMode(): Boolean {
+        var newMode = ServiceMode.NORMAL
+        try {
+            if (serviceMode == ServiceMode.VPN) {
+                newMode = ServiceMode.VPN
+            }
+        } catch (_: Exception) {
+        }
+        if (currentServiceMode == newMode) {
+            return false
+        }
+        currentServiceMode = newMode
+        return true
+    }
+
+    private suspend fun needVPNService(): Boolean {
+        val filePath = activeConfigPath
+        if (filePath.isBlank()) return false
+        val content = JSONObject(File(filePath).readText())
+        val inbounds = content.getJSONArray("inbounds")
+        for (index in 0 until inbounds.length()) {
+            val inbound = inbounds.getJSONObject(index)
+            if (inbound.getString("type") == "tun") {
+                return true
+            }
+        }
+        return false
+    }
+}
+