fix(installer,worker): service hosting, dark theme, uninstall polish

Worker:
- Wire UseWindowsService + Microsoft.Extensions.Hosting.WindowsServices so
  SCM's Service Control Protocol handshake succeeds. Previously the binary
  exited immediately under sc start, leaving the service registered but
  never running.

Installer:
- Pin SDK to .NET 9 (global.json) — SDK 10 dropped win-arm from its RID
  graph, breaking restore of the WPF project; .NET 9 keeps win-arm AND
  understands the .slnx solution format.
- Force SelfContained=true and default RID=win-x64 when PublishSingleFile
  is set, so Rider Publish and CLI produce the same bundle.
- Dark theme: set Background/Foreground explicitly on WizardWindow and
  SettingsWindow roots (WPF implicit styles don't cascade to derived
  Window types). Custom ComboBox template + ComboBoxItem style so
  dropdowns honour the dark palette instead of system defaults.
- Throttle download progress to one report per MB and overwrite the same
  UI line (\r prefix marker) instead of appending per chunk.
- Register ClaudeDo in HKLM\...\Uninstall so it appears in Apps & Features.
  Copy installer into InstallDir\uninstaller\ for the UninstallString, and
  schedule a cmd.exe trampoline to handle the self-delete case when
  Apps & Features launches the copy from inside the install dir.
- Treat sc.exe stop exit 1062 (ERROR_SERVICE_NOT_ACTIVE) as success.
- Delete the uninstall registry key during UninstallRunner.

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

src/ClaudeDo.Installer/Core/UninstallRunner.cs

@@ -1,6 +1,8 @@
+using System.Diagnostics;
 using System.IO;
 using ClaudeDo.Data;
 using ClaudeDo.Installer.Steps;
+using Microsoft.Win32;
 
 namespace ClaudeDo.Installer.Core;
 
@@ -36,6 +38,17 @@ public sealed class UninstallRunner
         progress.Report("Unregistering service...");
         await ProcessRunner.RunAsync("sc.exe", $"delete {StopServiceStep.ServiceName}", null, progress, ct);
 
+        // 3b) Remove Apps & Features registry entry (best-effort).
+        progress.Report("Removing Add/Remove Programs entry...");
+        try
+        {
+            Registry.LocalMachine.DeleteSubKeyTree(WriteUninstallRegistryStep.UninstallKeyPath, throwOnMissingSubKey: false);
+        }
+        catch (Exception ex)
+        {
+            progress.Report($"Warning: could not delete uninstall registry key: {ex.Message}");
+        }
+
         // 4) Remove shortcuts (best-effort — a stuck .lnk must not block the rest).
         progress.Report("Removing shortcuts...");
         TryDeleteFile(Path.Combine(
@@ -63,6 +76,21 @@ public sealed class UninstallRunner
                 failures.Add($"app data ({appData}): {err}");
         }
 
+        // 7) If we were launched from inside the install dir (Apps & Features case),
+        //    our own exe is still locked — schedule a cmd.exe trampoline to finish
+        //    the deletion after this process exits. Best-effort: if this fails the
+        //    user is left with an empty <uninstaller> folder which is harmless.
+        var runningExe = Environment.ProcessPath;
+        if (runningExe is not null
+            && IsInsideDirectory(runningExe, _context.InstallDirectory)
+            && Directory.Exists(_context.InstallDirectory))
+        {
+            progress.Report("Scheduling final cleanup after exit...");
+            TryScheduleTrampolineDelete(_context.InstallDirectory);
+            // The trampoline will finish the job — clear the residual failure entry for the install dir.
+            failures.RemoveAll(f => f.StartsWith("install dir"));
+        }
+
         if (failures.Count > 0)
         {
             return StepResult.Fail(
@@ -74,6 +102,37 @@ public sealed class UninstallRunner
         return StepResult.Ok();
     }
 
+    private static bool IsInsideDirectory(string filePath, string directory)
+    {
+        try
+        {
+            var full = Path.GetFullPath(filePath);
+            var dir = Path.GetFullPath(directory).TrimEnd(Path.DirectorySeparatorChar) + Path.DirectorySeparatorChar;
+            return full.StartsWith(dir, StringComparison.OrdinalIgnoreCase);
+        }
+        catch { return false; }
+    }
+
+    private static void TryScheduleTrampolineDelete(string installDir)
+    {
+        try
+        {
+            var pid = Environment.ProcessId;
+            // Wait for this process to exit, then recursively remove the install dir.
+            // /B timeout avoids a visible window; ping as a portable sleep; rmdir /S /Q is silent.
+            var cmd = $"/C start \"\" /MIN cmd /C \"ping 127.0.0.1 -n 3 >nul & rmdir /S /Q \"\"{installDir}\"\"\"";
+            Process.Start(new ProcessStartInfo
+            {
+                FileName = "cmd.exe",
+                Arguments = cmd,
+                UseShellExecute = false,
+                CreateNoWindow = true,
+                WindowStyle = ProcessWindowStyle.Hidden,
+            });
+        }
+        catch { /* best effort */ }
+    }
+
     /// <summary>
     /// Guards against catastrophic recursive-delete paths. The install dir must be
     /// a non-root directory with a non-empty name (e.g. reject "", "C:\\", "/").