fix(web): 修复扫描二维码后浮窗不显示的问题

- 在扫描二维码前隐藏所有浮窗- 扫描完成后重新显示最顶层浮窗
- 优化了浮窗显示逻辑，确保用户扫描后能够正确返回到应用

Author: ven-coder

assists-web/src/main/java/com/ven/assists/web/ASJavascriptInterface.kt

@@ -116,7 +116,9 @@ class ASJavascriptInterface(val webView: WebView) {
 
                 CallMethod.scanQR -> {
                     CoroutineWrapper.launch {
+                        AssistsWindowManager.hideAll()
                         val scanIntentResult = CustomFileProvider.requestLaunchersScan(ScanOptions())
+                        AssistsWindowManager.showTop()
                         callback(CallResponse<JsonObject>(code = 0, data = JsonObject().apply {
                             addProperty("value", scanIntentResult?.contents ?: "")
                         }, callbackId = request.callbackId))