Add Write-GitHub logging function for GitHub Actions (#29)

Implement a conditional logging utility that writes output only when running in GitHub Actions environment. Use it to
wrap application execution logs in GitHub Actions log groups.

Author: limbonaut

app-runner/Private/Logging.ps1

@@ -1,2 +1,15 @@
 # Logging Functions
-# This file is now empty as all public functions have been moved to the Public directory
+# This file contains internal logging utilities
+
+function Write-GitHub {
+    [CmdletBinding()]
+    param(
+        [Parameter(Mandatory = $true)]
+        [string]$Message
+    )
+
+    # Only write output if running in GitHub Actions
+    if ($env:GITHUB_ACTIONS -eq 'true') {
+        Write-Host $Message
+    }
+}

app-runner/Public/Invoke-DeviceApp.ps1

@@ -31,9 +31,13 @@ function Invoke-DeviceApp {
     Write-Debug "Running application: $ExecutablePath with arguments: $Arguments"
     Write-Debug "Target platform: $($script:CurrentSession.Platform)"
 
+    Write-GitHub "::group::Run log"
+
     # Use the provider to run the application
     $provider = $script:CurrentSession.Provider
     $result = $provider.RunApplication($ExecutablePath, $Arguments)
 
+    Write-GitHub "::endgroup::"
+
     return $result
-}
+}