Avalonia12 (#7)

* ava12升级

* Enable centralized package versioning

Add <Project> and <PropertyGroup> with <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally> to Directory.Packages.props to enable centralized package version management across the repository. This allows package versions to be controlled from this single file instead of individual project files.

* Migrate codebase to Avalonia 12 APIs

Apply Avalonia 12 migration changes: replace SystemDecorations with WindowDecorations and remove ExtendClientAreaChromeHints/ExtendClientAreaTitleBarHeightHint usages; update BindingPlugins removal logic (no-op); switch clipboard usage to ClipboardExtensions.SetTextAsync; update Bitmap.CopyPixels calls to the new signature. Replace TextBox.Watermark with PlaceholderText, convert NumberBox styles to FANumberBox and adjust templates, change Checked/Unchecked handlers to IsCheckedChanged, and adapt FluentIcons usages (SymbolIconSource -> FASymbol/FAFont/FluentIcon equivalents). Fix MainWindow partial classes to inherit Window and correct missing variables/fields/usings. Add migration docs/specs/tasks under .trae and include a small TestFluentIcons project for icon testing.

* Migrate to Avalonia 12 and Plugin SDK v5

Upgrade project to the Avalonia 12 baseline and Plugin SDK v5: centralize Avalonia packages, remove legacy WebView.Avalonia usage (use NativeWebView/WebView2 EnvironmentRequested), and update Fluent/Material icon/package usages. Bump multiple package/project versions to 5.0.0 and Avalonia 12.0.1, update plugin template and README/docs to SDK v5, and add PLUGIN_SDK_V5_MIGRATION.md.

Also fix runtime/behavior bugs: make DataLocationResolver use a fixed bootstrap launcher data path and avoid recursive ResolveDataRoot; add legacy-state handling and extraction in OobeStateService; and update component settings tests to reflect migrated storage (DB/backup) and reset cache for test reloads. Various csproj, tests, and docs updated to reflect the migration and ensure build/test compatibility.

* Update icon glyphs and symbol mappings

Replace and refine icon sources across settings pages and controls: many FAFontIconSource glyphs were updated to specific Seagull Fluent Icons codepoints, some FASymbolIconSource usages were replaced with FAFontIconSource, and a number of symbol-to-Symbol enum mappings were adjusted (e.g. "Bell" -> AlertOn, "Shield" -> ShieldLock). Also clarified a comment in SettingsWindow and fixed a trailing newline in StudySettingsPage. Changes standardize icon visuals and bridge FluentIcons glyphs into FluentAvalonia icon sources.

* fix.修复合并产生的问题。

LanMountainDesktop.Launcher/Views/DataLocationPromptWindow.axaml

@@ -3,13 +3,13 @@
         xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
         xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
         xmlns:views="clr-namespace:LanMountainDesktop.Launcher.Views"
-        xmlns:ui="using:FluentAvalonia.UI.Controls"
+        xmlns:fi="using:FluentIcons.Avalonia"
         mc:Ignorable="d"
         d:DesignWidth="520"
         d:DesignHeight="480"
         x:Class="LanMountainDesktop.Launcher.Views.DataLocationPromptWindow"
         x:DataType="views:DataLocationPromptWindow"
-        Title="选择数据保存位置"
+        Title="Choose Data Location"
         Width="520"
         Height="480"
         CanResize="False"
@@ -24,12 +24,13 @@
     </Grid.RenderTransform>
     <Grid Margin="36" RowDefinitions="Auto,*,Auto">
       <StackPanel Grid.Row="0" Spacing="8" Margin="0,0,0,20">
-        <TextBlock Text="选择数据保存位置"
+        <TextBlock Text="Choose Data Location"
                    FontSize="22"
                    FontWeight="SemiBold"
                    Foreground="{DynamicResource TextFillColorPrimaryBrush}" />
-        <TextBlock Text="决定将应用数据保存在哪里，可随时在设置中更改"
+        <TextBlock Text="Choose where launcher and desktop data should be stored. You can change this later in settings."
                    FontSize="13"
+                   TextWrapping="Wrap"
                    Foreground="{DynamicResource TextFillColorSecondaryBrush}" />
       </StackPanel>
 
@@ -41,15 +42,15 @@
                 IsVisible="False">
           <StackPanel Spacing="4">
             <StackPanel Orientation="Horizontal" Spacing="6">
-              <ui:SymbolIcon Symbol="Important"
+              <fi:SymbolIcon Symbol="Important"
                              FontSize="16"
                              Foreground="{DynamicResource SystemFillColorCriticalBrush}" />
-              <TextBlock Text="无法保存到应用目录"
+              <TextBlock Text="App folder is not writable"
                          FontWeight="SemiBold"
                          FontSize="13"
                          Foreground="{DynamicResource SystemFillColorCriticalBrush}" />
             </StackPanel>
-            <TextBlock Text="当前安装目录需要管理员权限才能写入，数据将自动保存到系统用户目录。"
+            <TextBlock Text="The current install directory requires elevated permissions. Data will be stored in the system user profile instead."
                        FontSize="12"
                        TextWrapping="Wrap"
                        Foreground="{DynamicResource SystemFillColorCriticalBrush}" />
@@ -70,11 +71,11 @@
                          GroupName="DataLocation"
                          IsChecked="True" />
             <StackPanel Grid.Column="1" Spacing="4">
-              <TextBlock Text="保存在系统用户目录（推荐）"
+              <TextBlock Text="Store in the system user profile (Recommended)"
                          FontSize="14"
                          FontWeight="SemiBold"
                          Foreground="{DynamicResource TextFillColorPrimaryBrush}" />
-              <TextBlock Text="数据与当前 Windows 用户绑定，重装应用或更新后数据不会丢失"
+              <TextBlock Text="Data stays tied to the current Windows user and remains intact across app reinstalls and updates."
                          FontSize="12"
                          TextWrapping="Wrap"
                          Foreground="{DynamicResource TextFillColorSecondaryBrush}" />
@@ -101,11 +102,11 @@
                          GroupName="DataLocation"
                          IsEnabled="False" />
             <StackPanel Grid.Column="1" Spacing="4">
-              <TextBlock Text="保存在应用安装目录"
+              <TextBlock Text="Store next to the app"
                          FontSize="14"
                          FontWeight="SemiBold"
                          Foreground="{DynamicResource TextFillColorPrimaryBrush}" />
-              <TextBlock Text="便于携带，可随应用文件夹整体移动到其他电脑"
+              <TextBlock Text="Useful for portable installs. The whole app folder can be moved to another machine together with its data."
                          FontSize="12"
                          TextWrapping="Wrap"
                          Foreground="{DynamicResource TextFillColorSecondaryBrush}" />
@@ -124,7 +125,7 @@
                 Padding="12,10"
                 IsVisible="False">
           <StackPanel Orientation="Horizontal" Spacing="6">
-            <ui:SymbolIcon Symbol="Message"
+            <fi:SymbolIcon Symbol="Info"
                            FontSize="16"
                            Foreground="{DynamicResource SystemFillColorSuccessBrush}" />
             <TextBlock x:Name="MigrationInfoText"
@@ -141,11 +142,11 @@
                   Spacing="10"
                   Margin="0,20,0,0">
         <Button x:Name="CancelButton"
-                Content="取消"
+                Content="Cancel"
                 Theme="{DynamicResource ButtonTheme}"
                 IsVisible="False" />
         <Button x:Name="ConfirmButton"
-                Content="确认"
+                Content="Confirm"
                 Theme="{DynamicResource AccentButtonTheme}" />
       </StackPanel>
     </Grid>