feat: 更新 WebView 数据目录，添加持久存储清理逻辑；优化 URL 生成和 H5 路由刷新时的品牌保持

android/app/src/main/kotlin/io/openim/flutter/openim/MainActivity.kt

@@ -13,6 +13,7 @@ import android.util.Base64
 import android.util.Log
 import android.webkit.ServiceWorkerController
 import android.webkit.WebSettings
+import android.webkit.WebStorage
 import android.webkit.WebView
 import androidx.core.content.FileProvider
 import io.flutter.embedding.android.FlutterActivity
@@ -30,10 +31,14 @@ class MainActivity : FlutterActivity() {
     private val WEBVIEW_CACHE_CHANNEL = "io.openim.flutter.im_webview_app/webview_cache"
     private val TAG = "MainActivity"
     private val MAX_BRANDING_ICON_SIZE = 192
-    private val WEBVIEW_DATA_DIRECTORY_SUFFIX = "h5_shell_fresh_profile_v2"
+    private val WEBVIEW_DATA_DIRECTORY_SUFFIX = "h5_shell_fresh_profile_v3"
+    private val WEBVIEW_STORAGE_RESET_PREFS = "h5_shell_webview_storage"
+    private val WEBVIEW_STORAGE_RESET_KEY = "reset_version"
+    private val WEBVIEW_STORAGE_RESET_VERSION = 3
 
     override fun onCreate(savedInstanceState: android.os.Bundle?) {
         configureWebViewDataDirectory()
+        clearWebViewPersistentStorageOnce()
         // 华为/荣耀/OPPO 等国产设备：在任意网络请求之前同步安装 Conscrypt，修复 SSL 握手失败（无 GMS 时系统 SSL 实现不完整）
         try {
             Security.insertProviderAt(Conscrypt.newProvider(), 1)
@@ -150,6 +155,46 @@ class MainActivity : FlutterActivity() {
         }
     }
 
+    private fun clearWebViewPersistentStorageOnce() {
+        val prefs = getSharedPreferences(WEBVIEW_STORAGE_RESET_PREFS, MODE_PRIVATE)
+        if (prefs.getInt(WEBVIEW_STORAGE_RESET_KEY, 0) >= WEBVIEW_STORAGE_RESET_VERSION) {
+            return
+        }
+
+        try {
+            WebStorage.getInstance().deleteAllData()
+            Log.d(TAG, "WebView persistent storage cleared")
+        } catch (e: Exception) {
+            Log.w(TAG, "WebView persistent storage clear failed: ${e.message}")
+        }
+
+        clearKnownWebViewCacheDirectories()
+        prefs.edit().putInt(WEBVIEW_STORAGE_RESET_KEY, WEBVIEW_STORAGE_RESET_VERSION).apply()
+    }
+
+    private fun clearKnownWebViewCacheDirectories() {
+        val cacheDirectoryNames = listOf(
+            "WebView",
+            "webview",
+            "org.chromium.android_webview",
+            "com.android.webview"
+        )
+
+        for (name in cacheDirectoryNames) {
+            val directory = File(cacheDir, name)
+            if (!directory.exists()) {
+                continue
+            }
+            try {
+                if (!directory.deleteRecursively()) {
+                    Log.w(TAG, "WebView cache directory delete returned false: ${directory.absolutePath}")
+                }
+            } catch (e: Exception) {
+                Log.w(TAG, "WebView cache directory delete failed: ${directory.absolutePath}, ${e.message}")
+            }
+        }
+    }
+
     private fun readLongArgument(value: Any?): Long? {
         return when (value) {
             is Int -> value.toLong()