Add scaling functionality for accessibility (#3505)

functions/private/Invoke-WinUtilFontScaling.ps1

@@ -0,0 +1,72 @@
+function Invoke-WinUtilFontScaling {
+    <#
+
+    .SYNOPSIS
+        Applies UI and font scaling for accessibility
+
+    .PARAMETER ScaleFactor
+        Sets the scaling from 0.75 and 2.0.
+        Default is 1.0 (100% - no scaling)
+
+    .EXAMPLE
+        Invoke-WinUtilFontScaling -ScaleFactor 1.25
+        # Applies 125% scaling
+    #>
+
+    param (
+        [double]$ScaleFactor = 1.0
+    )
+
+    # Validate if scale factor is within the range
+    if ($ScaleFactor -lt 0.75 -or $ScaleFactor -gt 2.0) {
+        Write-Warning "Scale factor must be between 0.75 and 2.0. Using 1.0 instead."
+        $ScaleFactor = 1.0
+    }
+
+    # Define an array for resources to be scaled
+    $fontResources = @(
+        "FontSize",
+        "ButtonFontSize",
+        "HeaderFontSize",
+        "TabButtonFontSize",
+        "IconFontSize",
+        "SettingsIconFontSize",
+        "CloseIconFontSize",
+        "AppEntryFontSize",
+        "SearchBarTextBoxFontSize",
+        "SearchBarClearButtonFontSize",
+        "CustomDialogFontSize",
+        "CustomDialogFontSizeHeader",
+        "ConfigUpdateButtonFontSize",
+        "CheckBoxBulletDecoratorSize"
+    )
+
+    # Apply scaling to each resource
+    foreach ($resourceName in $fontResources) {
+        try {
+            # Get the default font size from the theme configuration
+            $originalValue = $sync.configs.themes.shared.$resourceName
+            if ($originalValue) {
+                # Convert string to double since values are stored as strings
+                $originalValue = [double]$originalValue
+                # Calculates and applies the new font size
+                $newValue = [math]::Round($originalValue * $ScaleFactor, 1)
+                $sync.Form.Resources[$resourceName] = $newValue
+                Write-Debug "Scaled $resourceName from original $originalValue to $newValue (factor: $ScaleFactor)"
+            }
+        }
+        catch {
+            Write-Warning "Failed to scale resource $resourceName : $_"
+        }
+    }
+
+    # Update the font scaling percentage displayed on the UI
+    if ($sync.FontScalingValue) {
+        $percentage = [math]::Round($ScaleFactor * 100)
+        $sync.FontScalingValue.Text = "$percentage%"
+    }
+
+    Write-Debug "Font scaling applied with factor: $ScaleFactor"
+}
+
+