fix(reporting): add Platform column and clean up Windows artifacts

- Export-SettingsReport.py: add Platform column for Settings Catalog
  (platforms field) and legacy policies (platform/platformType or
  @odata.type inference)
- MSGraph.psm1: store GraphMetaData.xml in cross-platform data folder
  (Get-CloudApiDataFolder) instead of literal %LOCALAPPDATA% path
- MSALAuthentication.psm1: skip TokenCacheHelperEx on non-Windows with
  an info log instead of failing on missing ProtectedData.dll
- .gitignore: remove literal %LOCALAPPDATA% patterns
- AGENTS.md, CHANGELOG: document reporting and cross-platform fixes

Extensions/MSALAuthentication.psm1

@@ -554,7 +554,12 @@ function Add-MSALPrereq
         }
     }
 
-    if (-not ("TokenCacheHelperEx" -as [type])) 
+    if (-not (Test-IsWindowsPlatform))
+    {
+        $global:SkipTokenCacheHelperEx = $true
+        Write-Log "Token cache serialization is only supported on Windows. Skipping TokenCacheHelperEx."
+    }
+    elseif (-not ("TokenCacheHelperEx" -as [type])) 
     {
         [System.Collections.Generic.List[string]] $RequiredAssemblies = New-Object System.Collections.Generic.List[string]
 
@@ -723,23 +728,31 @@ function Add-MSALPrereq_old
         $script:msalFile = $msalPath
     }
 
-    $RequiredAssemblies.Add('System.Security.dll')
-    $RequiredAssemblies.Add('mscorlib.dll')
-    if($PSVersionTable.PSVersion.Major -ge 7)
-    {        
-        $RequiredAssemblies.Add('System.Security.Cryptography.ProtectedData.dll')
-    }
-    
-    $RequiredAssemblies.Add('System.Threading.dll')
-
-    try
-    {
-        Add-Type -Path ($global:AppRootFolder + "\CS\TokenCacheHelperEx.cs") -ReferencedAssemblies $RequiredAssemblies
-    }
-    catch
+    if (-not (Test-IsWindowsPlatform))
     {
         $global:SkipTokenCacheHelperEx = $true
-        Write-LogError "Failed to compile TokenCacheHelperEx. The access token will not be cached. Check write access to the CS folder and ASR policies" $_.Exception
+        Write-Log "Token cache serialization is only supported on Windows. Skipping TokenCacheHelperEx."
+    }
+    else
+    {
+        $RequiredAssemblies.Add('System.Security.dll')
+        $RequiredAssemblies.Add('mscorlib.dll')
+        if($PSVersionTable.PSVersion.Major -ge 7)
+        {        
+            $RequiredAssemblies.Add('System.Security.Cryptography.ProtectedData.dll')
+        }
+        
+        $RequiredAssemblies.Add('System.Threading.dll')
+
+        try
+        {
+            Add-Type -Path ($global:AppRootFolder + "\CS\TokenCacheHelperEx.cs") -ReferencedAssemblies $RequiredAssemblies
+        }
+        catch
+        {
+            $global:SkipTokenCacheHelperEx = $true
+            Write-LogError "Failed to compile TokenCacheHelperEx. The access token will not be cached. Check write access to the CS folder and ASR policies" $_.Exception
+        }
     }
     if(Test-IsWindowsPlatform)
     {