fix: resolve critical bugs and improve reliability across worker, data, UI

- Fix worker using wrong DB by defaulting to CurrentUser service account
  and expanding ~ to absolute paths at install time
- Fix DbContext disposed before fire-and-forget by passing taskId instead
  of TaskEntity into RunInSlotAsync, which creates its own context
- Fix ActiveTaskDto property casing mismatch between hub and client
- Move WAL mode PRAGMA before migrations to prevent concurrent lock issues
- Replace FirstAsync with FirstOrDefaultAsync + null guards in tag operations
- Add delete confirmation flow for lists
- Log fire-and-forget exceptions instead of swallowing them
- Broadcast RunCreated event from WorkerHub.RunNow
- Add IDisposable to MainWindowViewModel for event handler cleanup
- Preserve subtask CreatedAt on updates instead of overwriting
- Replace bare catch blocks with Debug.WriteLine logging

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

src/ClaudeDo.Installer/Core/InstallContext.cs

@@ -22,7 +22,7 @@ public sealed class InstallContext
     public int SignalRPort { get; set; } = 47_821;
     public int QueueBackstopIntervalMs { get; set; } = 30_000;
     public string ClaudeBin { get; set; } = "claude";
-    public string ServiceAccount { get; set; } = "LocalSystem";
+    public string ServiceAccount { get; set; } = "CurrentUser";
     public bool AutoStart { get; set; } = true;
     public int RestartDelayMs { get; set; } = 5000;
 

src/ClaudeDo.Installer/Steps/WriteConfigStep.cs

@@ -1,3 +1,4 @@
+using ClaudeDo.Data;
 using ClaudeDo.Installer.Core;
 
 namespace ClaudeDo.Installer.Steps;
@@ -10,13 +11,15 @@ public sealed class WriteConfigStep : IInstallStep
     {
         try
         {
+            // Expand ~ to the installing user's absolute path so the worker
+            // service always finds the correct DB regardless of service account.
             var workerCfg = new InstallerWorkerConfig
             {
-                DbPath = ctx.DbPath,
-                SandboxRoot = ctx.SandboxRoot,
-                LogRoot = ctx.LogRoot,
+                DbPath = Paths.Expand(ctx.DbPath),
+                SandboxRoot = Paths.Expand(ctx.SandboxRoot),
+                LogRoot = Paths.Expand(ctx.LogRoot),
                 WorktreeRootStrategy = ctx.WorktreeRootStrategy,
-                CentralWorktreeRoot = ctx.CentralWorktreeRoot,
+                CentralWorktreeRoot = Paths.Expand(ctx.CentralWorktreeRoot),
                 QueueBackstopIntervalMs = ctx.QueueBackstopIntervalMs,
                 SignalRPort = ctx.SignalRPort,
                 ClaudeBin = ctx.ClaudeBin,