fix(data-table): multiple expandTrigger with tree data

CHANGELOG.en-US.md

@@ -1,5 +1,11 @@
 # CHANGELOG
 
+## NEXT_VERSION
+
+### Fixes
+
+- Fix `n-data-table` multiple expandTrigger with tree data.
+
 ## 2.40.3
 
 `2024-12-02`

CHANGELOG.zh-CN.md

@@ -5,6 +5,7 @@
 ### Fixes
 
 - 修复 `n-scrollbar`、`n-float-button`、`n-float-button-group`、`n-popover` 组件中的 `inset` 属性在部分浏览器中有兼容性问题，close [#6604](https://github.com/tusen-ai/naive-ui/issues/6604)，close [#6602](https://github.com/tusen-ai/naive-ui/issues/6602)
+- 修复 `n-data-table`在使用树形数据的时候出现多个扩展icon的问题
 
 ## 2.40.3
 

src/data-table/src/TableParts/Body.tsx

@@ -785,8 +785,8 @@ export default defineComponent({
               const virtualXRowHeight = isVirtualX
                 ? pxfy(heightForRow?.(rowData, actualRowIndex) || minRowHeight)
                 : undefined
-              const cells = iteratedCols.map((col) => {
-                const colIndex = col.index
+              const cells = iteratedCols.map((col, colIdx) => {
+                const colIndex = isVirtualX ? col.index : colIdx
                 if (displayedRowIndex in cordToPass) {
                   const cordOfRowToPass = cordToPass[displayedRowIndex]
                   const indexInCordOfRowToPass