fix: Use AppContext.BaseDirectory instead of Environment.CurrentDirectory (#21797)

#21750
---------
Co-authored-by: Eilon Lipton <[email protected]>
Co-authored-by: Jonathan Peppers <[email protected]>

Author: 3 people

src/BlazorWebView/src/WindowsForms/BlazorWebView.cs

@@ -177,7 +177,7 @@ private void StartWebViewCoreIfPossible()
 			}
 			else
 			{
-				appRootDir = Environment.CurrentDirectory;
+				appRootDir = AppContext.BaseDirectory;
 			}
 			var hostPageFullPath = Path.GetFullPath(Path.Combine(appRootDir, HostPage!)); // HostPage is nonnull because RequiredStartupPropertiesSet is checked above
 			var contentRootDirFullPath = Path.GetDirectoryName(hostPageFullPath)!;

src/BlazorWebView/src/Wpf/BlazorWebView.cs

@@ -262,7 +262,7 @@ private void StartWebViewCoreIfPossible()
 			}
 			else
 			{
-				appRootDir = Environment.CurrentDirectory;
+				appRootDir = AppContext.BaseDirectory;
 			}
 			var hostPageFullPath = Path.GetFullPath(Path.Combine(appRootDir, HostPage));
 			var contentRootDirFullPath = Path.GetDirectoryName(hostPageFullPath)!;