doc: 增加文档

Author: ArgoZhang

src/BootstrapBlazor.Server/Locales/en-US.json

@@ -3088,7 +3088,9 @@
     "MultiSelectVirtualizeDescription": "Component virtual scrolling supports two ways of providing data through <code>Items</code> or <code>OnQueryAsync</code> callback methods",
     "MultiSelectsAttribute_ShowSearch": "Whether to display the search box",
     "MultiSelectsAttribute_IsVirtualize": "Wether to enable virtualize",
-    "MultiSelectsAttribute_DefaultVirtualizeItemText": "The text string corresponding to the first load value when virtual scrolling is turned on is separated by commas"
+    "MultiSelectsAttribute_DefaultVirtualizeItemText": "The text string corresponding to the first load value when virtual scrolling is turned on is separated by commas",
+    "MultiSelectGenericTitle": "Generic",
+    "MultiSelectGenericIntro": "Data source <code>Items</code> supports generics when using <code>SelectedItem&lt;TValue&gt;</code>"
   },
   "BootstrapBlazor.Server.Components.Samples.Radios": {
     "RadiosTitle": "Radio",

src/BootstrapBlazor.Server/Locales/zh-CN.json

@@ -3088,7 +3088,9 @@
     "MultiSelectVirtualizeDescription": "组件虚拟滚动支持两种形式通过 <code>Items</code> 或者 <code>OnQueryAsync</code> 回调方法提供数据",
     "MultiSelectsAttribute_ShowSearch": "是否显示搜索框",
     "MultiSelectsAttribute_IsVirtualize": "是否开启虚拟滚动",
-    "MultiSelectsAttribute_DefaultVirtualizeItemText": "开启虚拟滚动时首次加载 Value 对应的文本字符串用逗号分割"
+    "MultiSelectsAttribute_DefaultVirtualizeItemText": "开启虚拟滚动时首次加载 Value 对应的文本字符串用逗号分割",
+    "MultiSelectGenericTitle": "泛型支持",
+    "MultiSelectGenericIntro": "数据源 <code>Items</code> 使用 <code>SelectedItem&lt;TValue&gt;</code> 时即可支持泛型"
   },
   "BootstrapBlazor.Server.Components.Samples.Radios": {
     "RadiosTitle": "Radio 单选框",