Rewrite as standalone C# WinForms app

Replace the Office Web Add-in with a native Windows application.
The web add-in required Exchange/M365 for registration which is
not available in all customer environments (standalone Office,
POP/IMAP only).

The new app:
- Uses COM Interop to access Outlook contacts directly
- Communicates with Starface REST API (accepts self-signed certs)
- Runs as System Tray app with optional auto-sync
- Profile-based config stored in %AppData%
- No webserver, no certificates, no Exchange, no M365 needed
- Inno Setup installer for clean MSI-style deployment
- Works with any Outlook version (Classic and New)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/StarfaceOutlookSync/UI/SyncProgressForm.cs

@@ -0,0 +1,127 @@
+using System;
+using System.Drawing;
+using System.Threading.Tasks;
+using System.Windows.Forms;
+using StarfaceOutlookSync.Models;
+using StarfaceOutlookSync.Services;
+
+namespace StarfaceOutlookSync.UI
+{
+    public class SyncProgressForm : Form
+    {
+        private readonly SyncProfile _profile;
+        private readonly SyncEngine _engine = new SyncEngine();
+        private TextBox _txtLog;
+        private ProgressBar _progressBar;
+        private Button _btnClose, _btnStart;
+        private Label _lblResult;
+
+        public SyncProgressForm(SyncProfile profile)
+        {
+            _profile = profile;
+            InitializeComponent();
+        }
+
+        private void InitializeComponent()
+        {
+            Text = $"Synchronisation - {_profile.Name}";
+            Size = new Size(500, 400);
+            FormBorderStyle = FormBorderStyle.FixedDialog;
+            MaximizeBox = false;
+            MinimizeBox = false;
+            StartPosition = FormStartPosition.CenterParent;
+            Font = new Font("Segoe UI", 9);
+
+            var infoLabel = new Label
+            {
+                Text = $"{_profile.StarfaceConnection.Host} ({_profile.StarfaceAddressBook.Name}) <-> {_profile.OutlookFolderName}",
+                Left = 12, Top = 12, Width = 460, AutoSize = false, Height = 20
+            };
+
+            _progressBar = new ProgressBar
+            {
+                Left = 12, Top = 38, Width = 460, Height = 22,
+                Style = ProgressBarStyle.Marquee
+            };
+
+            _txtLog = new TextBox
+            {
+                Left = 12, Top = 68, Width = 460, Height = 200,
+                Multiline = true, ReadOnly = true, ScrollBars = ScrollBars.Vertical,
+                BackColor = Color.FromArgb(30, 30, 30), ForeColor = Color.FromArgb(212, 212, 212),
+                Font = new Font("Consolas", 9)
+            };
+
+            _lblResult = new Label
+            {
+                Left = 12, Top = 276, Width = 460, Height = 40,
+                AutoSize = false, ForeColor = Color.Gray
+            };
+
+            _btnStart = new Button
+            {
+                Text = "Synchronisation starten", Left = 12, Top = 322, Width = 180, Height = 30
+            };
+            _btnStart.Click += async (s, e) => await RunSync();
+
+            _btnClose = new Button
+            {
+                Text = "Schliessen", Left = 380, Top = 322, Width = 90, Height = 30,
+                DialogResult = DialogResult.Cancel
+            };
+
+            Controls.AddRange(new Control[] { infoLabel, _progressBar, _txtLog, _lblResult, _btnStart, _btnClose });
+            CancelButton = _btnClose;
+        }
+
+        private void AppendLog(string message)
+        {
+            if (InvokeRequired)
+            {
+                Invoke(new Action(() => AppendLog(message)));
+                return;
+            }
+            _txtLog.AppendText($"[{DateTime.Now:HH:mm:ss}] {message}\r\n");
+        }
+
+        private async Task RunSync()
+        {
+            _btnStart.Enabled = false;
+            _btnClose.Enabled = false;
+            _progressBar.Style = ProgressBarStyle.Marquee;
+            _lblResult.Text = "";
+
+            _engine.OnProgress += AppendLog;
+
+            try
+            {
+                var result = await Task.Run(() => _engine.SyncProfileAsync(_profile));
+
+                _progressBar.Style = ProgressBarStyle.Blocks;
+                _progressBar.Value = 100;
+
+                var resultText = $"Erstellt: {result.Created}  |  Aktualisiert: {result.Updated}  |  Fehler: {result.Errors}";
+                _lblResult.Text = resultText;
+                _lblResult.ForeColor = result.Errors > 0 ? Color.OrangeRed : Color.Green;
+
+                if (result.ErrorMessages.Count > 0)
+                {
+                    AppendLog("--- Fehler ---");
+                    foreach (var err in result.ErrorMessages)
+                        AppendLog(err);
+                }
+            }
+            catch (Exception ex)
+            {
+                _lblResult.Text = $"Fehler: {ex.Message}";
+                _lblResult.ForeColor = Color.Red;
+                AppendLog($"FEHLER: {ex.Message}");
+            }
+
+            _engine.OnProgress -= AppendLog;
+            _btnStart.Enabled = true;
+            _btnStart.Text = "Erneut synchronisieren";
+            _btnClose.Enabled = true;
+        }
+    }
+}