Fix SA1616: Add text to empty return value documentation (#46718)

Add meaningful descriptions to 6 empty returns XML doc tags across DSC,
CmdPal, and Extensions.Toolkit.

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

.github/actions/spell-check/allow/code.txt

@@ -48,7 +48,6 @@ nupkg
 petabyte
 resw
 resx
-runtimeconfig
 srt
 Stereolithography
 terabyte
@@ -341,6 +340,29 @@ WINEVENTPROC
 WORKERW
 FULLSCREENAPP
 
+# COM/WinRT interface prefixes and type fragments
+BAlt
+BShift
+Cmanifest
+Cmodule
+Cuuid
+Dng
+IApplication
+IDisposable
+IEnum
+IFolder
+IInitialize
+IMemory
+IOle
+ipreview
+IProperty
+IShell
+ithumbnail
+IVirtual
+
+# Test frameworks
+MSTEST
+
 # PowerRename metadata pattern abbreviations (used in tests and regex patterns)
 DDDD
 FFF