Optimize LuckyExcel xlsx preview conversion with Web Worker (#766)

* Optimize LuckyExcel conversion with worker

* Fallback LuckyExcel worker errors to main thread

server/src/main/resources/static/xlsx/luckyexcel-worker.js

@@ -0,0 +1,54 @@
+// LuckyExcel's bundled getBinaryContent reads window.XMLHttpRequest.
+// Web Worker exposes XMLHttpRequest on self, so provide a minimal window alias
+// before loading the UMD bundle.
+self.window = self;
+
+importScripts('./luckyexcel.umd.js');
+
+self.console.log = function () {};
+
+self.onmessage = function (event) {
+    var data = event.data || {};
+    var url = data.url;
+    var name = data.name;
+
+    if (!url) {
+        self.postMessage({
+            type: 'error',
+            message: '文件URL为空'
+        });
+        return;
+    }
+
+    try {
+        LuckyExcel.transformExcelToLuckyByUrl(
+            url,
+            name,
+            function (exportJson, luckysheetfile) {
+                if (!exportJson || !exportJson.sheets || exportJson.sheets.length === 0) {
+                    self.postMessage({
+                        type: 'error',
+                        message: '读取excel文件内容失败!'
+                    });
+                    return;
+                }
+
+                self.postMessage({
+                    type: 'success',
+                    exportJson: exportJson
+                });
+            },
+            function (error) {
+                self.postMessage({
+                    type: 'error',
+                    message: error && error.message ? error.message : String(error)
+                });
+            }
+        );
+    } catch (error) {
+        self.postMessage({
+            type: 'error',
+            message: error && error.message ? error.message : String(error)
+        });
+    }
+};

server/src/main/resources/static/xlsx/luckyexcel.umd.js

@@ -3938,7 +3938,7 @@ var LuckySheet = /** @class */function (_super) {
     _this.sheetList = allFileOption.sheetList;
     _this.imageList = allFileOption.imageList;
     _this.hide = allFileOption.hide;
-    console.log(allFileOption, 'allFileOption');
+    // console.log(allFileOption, 'allFileOption');
     _this.dataVerificationSelectCount = allFileOption.dataVerificationSelectCount;
     //Output
     _this.name = sheetName;