feat(tasks): mark tasks and lists as manual

Reminders written down as todos had no home: every task looked like Claude work.
A manual task now shows a MANUAL badge and hides send-to-queue, refine and the
planning session; the queue picker, daily prep and the list handler all skip it,
with a TaskStateService guard so the MCP surface and hub cannot start one either.
Opening a hand-driven ConPTY session stays available on purpose.

A list can be marked manual in its settings, which makes tasks created there
(UI and MCP add_task) start out manual. Toggle per task from its context menu.

src/ClaudeDo.Worker/State/TaskStateService.cs

@@ -41,6 +41,9 @@ public sealed class TaskStateService : ITaskStateService
         if (await IsDraftChildAsync(ctx, taskId, ct))
             return new TransitionResult(false, "Draft subtask: finalize the plan before queuing it.");
 
+        if (await IsManualAsync(ctx, taskId, ct))
+            return new TransitionResult(false, "Manual task: mark it as a Claude task before queuing it.");
+
         var affected = await ctx.Tasks
             .Where(t => t.Id == taskId && t.Status != TaskStatus.Running)
             .ExecuteUpdateAsync(s => s.SetProperty(t => t.Status, TaskStatus.Queued), ct);
@@ -60,6 +63,9 @@ public sealed class TaskStateService : ITaskStateService
         if (await IsDraftChildAsync(ctx, taskId, ct))
             return new TransitionResult(false, "Draft subtask: finalize the plan before running it.");
 
+        if (await IsManualAsync(ctx, taskId, ct))
+            return new TransitionResult(false, "Manual task: mark it as a Claude task before running it.");
+
         var affected = await ctx.Tasks
             .Where(t => t.Id == taskId && t.Status != TaskStatus.Running)
             .ExecuteUpdateAsync(s => s
@@ -418,6 +424,11 @@ public sealed class TaskStateService : ITaskStateService
     // A subtask is "draft" only while its planning parent has an open (Active) session.
     // Improvement children whose parent has PlanningPhase.None are not drafts and may be
     // queued freely. Standalone tasks (no parent) are never draft.
+    // Server-side backstop for the manual flag: the UI hides the hand-off affordances, but the
+    // MCP surface and hub can still be driven directly.
+    private static Task<bool> IsManualAsync(ClaudeDoDbContext ctx, string taskId, CancellationToken ct)
+        => ctx.Tasks.AsNoTracking().AnyAsync(t => t.Id == taskId && t.IsManual, ct);
+
     private static async Task<bool> IsDraftChildAsync(ClaudeDoDbContext ctx, string taskId, CancellationToken ct)
     {
         var parentId = await ctx.Tasks.AsNoTracking()