ci: add self-contained publish for Avalonia build

- Add Net9.0-SelfContained.pubxml publish profile for Avalonia
- Add Publish-Self-Contained-Avalonia function to post_build.ps1
- Call Avalonia publish before cleanup in Main function

Flow.Launcher.Avalonia/Properties/PublishProfiles/Net9.0-SelfContained.pubxml

@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!--
+https://go.microsoft.com/fwlink/?LinkID=208121.
+-->
+<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
+  <PropertyGroup>
+    <PublishProtocol>FileSystem</PublishProtocol>
+    <Configuration>Release</Configuration>
+    <Platform>Any CPU</Platform>
+    <TargetFramework>net9.0-windows10.0.19041.0</TargetFramework>
+    <PublishDir>..\Output\Release\Avalonia\</PublishDir>
+    <RuntimeIdentifier>win-x64</RuntimeIdentifier>
+    <SelfContained>true</SelfContained>
+    <PublishSingleFile>False</PublishSingleFile>
+    <PublishReadyToRun>False</PublishReadyToRun>
+    <PublishTrimmed>False</PublishTrimmed>
+  </PropertyGroup>
+</Project>

Scripts/post_build.ps1

@@ -135,6 +135,24 @@ function Publish-Self-Contained ($p) {
     dotnet publish -c Release $csproj /p:PublishProfile=$profile
 }
 
+function Publish-Self-Contained-Avalonia ($p) {
+    $csproj  = "$p\Flow.Launcher.Avalonia\Flow.Launcher.Avalonia.csproj"
+    $profile = "$p\Flow.Launcher.Avalonia\Properties\PublishProfiles\Net9.0-SelfContained.pubxml"
+
+    if (!(Test-Path $csproj)) {
+        Write-Host "Avalonia project not found at $csproj, skipping self-contained publish..."
+        return
+    }
+
+    if (!(Test-Path $profile)) {
+        Write-Host "Avalonia publish profile not found at $profile, skipping self-contained publish..."
+        return
+    }
+
+    Write-Host "Publishing Avalonia self-contained..."
+    dotnet publish -c Release $csproj /p:PublishProfile=$profile
+}
+
 function Publish-Portable ($outputLocation, $version) {
 
     & $outputLocation\Flow-Launcher-Setup.exe --silent | Out-Null
@@ -156,6 +174,7 @@ function Main {
         Remove-CreateDumpExe $p $config
 
         # Process Avalonia build
+        Publish-Self-Contained-Avalonia $p
         Delete-Unused-Avalonia $p $config
         Remove-CreateDumpExe-Avalonia $p $config