Move Backend Storage to Interactive User Profile

Resolves backend SQLite/config storage from the logged-on Windows user instead of LOCAL SYSTEM and migrates existing systemprofile backend files when needed.

Data/DatabasePath.cs

@@ -1,4 +1,5 @@
 using System.IO;
+using UtopiaCanteenSystem.Services.Logging;
 
 namespace UtopiaCanteenSystem.Data;
 
@@ -11,6 +12,7 @@ public static class DatabasePath
     private static string? _appDataFolder;
     private static string? _dbPath;
     private static string _productFolderName = "UtopiaCanteenSystem";
+    private static bool _useInteractiveLocalAppData;
 
     /// <summary>
     /// Use "UtopiaCanteenBackend" for the Windows Service; default is legacy WPF folder name.
@@ -18,6 +20,7 @@ public static class DatabasePath
     public static void UseBackendServiceStorage()
     {
         _productFolderName = "UtopiaCanteenBackend";
+        _useInteractiveLocalAppData = true;
         _appDataFolder = null;
         _dbPath = null;
     }
@@ -25,6 +28,7 @@ public static class DatabasePath
     public static void UseClientStorage()
     {
         _productFolderName = "UtopiaCanteenClient";
+        _useInteractiveLocalAppData = false;
         _appDataFolder = null;
         _dbPath = null;
     }
@@ -37,11 +41,63 @@ public static class DatabasePath
         if (_appDataFolder != null)
             return _appDataFolder;
 
-        _appDataFolder = Path.Combine(
+        var localAppDataRoot = ResolveLocalAppDataRoot();
+        _appDataFolder = Path.Combine(localAppDataRoot, _productFolderName);
+        Directory.CreateDirectory(_appDataFolder);
+        MigrateBackendSystemProfileStorageIfNeeded(_appDataFolder);
+        return _appDataFolder;
+    }
+
+    private static string ResolveLocalAppDataRoot()
+    {
+        if (_useInteractiveLocalAppData)
+        {
+            var interactive = InteractiveUserPath.TryGetLocalAppDataPath();
+            if (!string.IsNullOrWhiteSpace(interactive))
+                return interactive;
+        }
+
+        return Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData);
+    }
+
+    private static void MigrateBackendSystemProfileStorageIfNeeded(string newFolder)
+    {
+        if (!_useInteractiveLocalAppData)
+            return;
+
+        var systemProfileFolder = Path.Combine(
             Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
             _productFolderName);
-        Directory.CreateDirectory(_appDataFolder);
-        return _appDataFolder;
+
+        if (string.Equals(systemProfileFolder, newFolder, StringComparison.OrdinalIgnoreCase) ||
+            !Directory.Exists(systemProfileFolder))
+            return;
+
+        var oldDbPath = Path.Combine(systemProfileFolder, "utopia_canteen.db");
+        var newDbPath = Path.Combine(newFolder, "utopia_canteen.db");
+        if (File.Exists(oldDbPath) && !File.Exists(newDbPath))
+        {
+            CopyIfMissing(oldDbPath, newDbPath);
+            CopyIfMissing(Path.Combine(systemProfileFolder, "utopia_canteen.db-wal"), Path.Combine(newFolder, "utopia_canteen.db-wal"));
+            CopyIfMissing(Path.Combine(systemProfileFolder, "utopia_canteen.db-shm"), Path.Combine(newFolder, "utopia_canteen.db-shm"));
+        }
+
+        CopyIfMissing(Path.Combine(systemProfileFolder, "backend-settings.json"), Path.Combine(newFolder, "backend-settings.json"));
+    }
+
+    private static void CopyIfMissing(string sourcePath, string destinationPath)
+    {
+        if (!File.Exists(sourcePath) || File.Exists(destinationPath))
+            return;
+
+        try
+        {
+            File.Copy(sourcePath, destinationPath);
+        }
+        catch
+        {
+            // If migration fails, the app will continue with files already present or create new ones.
+        }
     }
 
     /// <summary>

Services/Logging/InteractiveUserPath.cs

@@ -7,7 +7,7 @@ namespace UtopiaCanteenSystem.Services.Logging;
 /// <summary>
 /// Resolves the logged-on Windows user's profile paths when the app runs as a service (SYSTEM).
 /// </summary>
-internal static class InteractiveUserPath
+public static class InteractiveUserPath
 {
     public static string? TryGetLocalAppDataPath()
     {