Delete tasks from the board

Adds DELETE /api/orgboard/tasks/{id} (WorkTasks permission) and a "Delete task" button
in the task drawer (with confirm). Children are detached (kept as top-level) rather than
deleted; status-transition history is dropped. There was previously no way to remove a task.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

client/src/pages/BoardPage.tsx

@@ -8,7 +8,7 @@ import {
   useSensors,
   type DragEndEvent,
 } from '@dnd-kit/core'
-import { Bot, Plus } from 'lucide-react'
+import { Bot, Plus, Trash2 } from 'lucide-react'
 import { toast } from 'sonner'
 import { AppShell } from '@/components/AppShell'
 import { Badge } from '@/components/ui/badge'
@@ -554,6 +554,21 @@ function TaskDrawer({
             </div>
           </div>
         )}
+
+        <div className="mt-2 border-t pt-4">
+          <Button
+            variant="destructive"
+            size="sm"
+            disabled={busy}
+            onClick={() => {
+              if (window.confirm(`Delete "${task.title}"? This can't be undone.`)) {
+                act(() => api.del(`/api/orgboard/tasks/${task.id}`), 'Task deleted.').then(onClose)
+              }
+            }}
+          >
+            <Trash2 data-icon="inline-start" /> Delete task
+          </Button>
+        </div>
       </SheetContent>
     </Sheet>
   )

src/Modules/TeamUp.Modules.OrgBoard/Domain/WorkItem.cs

@@ -69,6 +69,9 @@ internal sealed class WorkItem : Entity
         UpdatedAtUtc = nowUtc;
     }
 
+    /// <summary>Detach from a parent (used when the parent is deleted, so the child stays on the board).</summary>
+    public void ClearParent() => ParentId = null;
+
     /// <summary>Appends an approved agent artifact (spec / test plan) to the task.</summary>
     public void AttachArtifact(string content, DateTimeOffset nowUtc)
     {

src/Modules/TeamUp.Modules.OrgBoard/Endpoints/OrgBoardEndpoints.cs

@@ -30,6 +30,7 @@ internal static class OrgBoardEndpoints
         group.MapGet("/board", GetBoard).RequireAuthorization();
         group.MapPatch("/tasks/{id:guid}/move", MoveTask).RequireAuthorization();
         group.MapPatch("/tasks/{id:guid}/assign", AssignTask).RequireAuthorization();
+        group.MapDelete("/tasks/{id:guid}", DeleteTask).RequireAuthorization();
         group.MapGet("/cartable", Cartable).RequireAuthorization();
 
         group.MapPost("/seats", CreateSeat).RequireAuthorization();
@@ -273,6 +274,36 @@ internal static class OrgBoardEndpoints
         return Results.Ok(ToResponse(item));
     }
 
+    // Remove a task from the board. Its children are detached (kept as top-level) rather than deleted,
+    // and its status-transition history is dropped. Any agent runs/reviews it spawned are left as history.
+    private static async Task<IResult> DeleteTask(
+        Guid id, ICurrentUser user, IPermissionService permissions,
+        IAuditLog audit, OrgBoardDbContext db, CancellationToken ct)
+    {
+        var item = await db.WorkItems.FirstOrDefaultAsync(w => w.Id == id, ct);
+        if (item is null)
+        {
+            return Results.NotFound();
+        }
+
+        var team = await db.Teams.FirstOrDefaultAsync(t => t.Id == item.TeamId, ct);
+        if (team is null || !permissions.Has(Capability.WorkTasks, ScopeRef.Team(item.TeamId), ScopeRef.Org(team.OrganizationId)))
+        {
+            return Results.Forbid();
+        }
+
+        foreach (var child in await db.WorkItems.Where(w => w.ParentId == id).ToListAsync(ct))
+        {
+            child.ClearParent();
+        }
+
+        db.Transitions.RemoveRange(await db.Transitions.Where(t => t.WorkItemId == id).ToListAsync(ct));
+        db.WorkItems.Remove(item);
+        await db.SaveChangesAsync(ct);
+        await audit.WriteAsync(new AuditEvent("task.deleted", "WorkItem", id, user.MemberId, item.Title), ct);
+        return Results.NoContent();
+    }
+
     private static async Task<IResult> GetBoard(
         Guid teamId, IPermissionService permissions, OrgBoardDbContext db, CancellationToken ct)
     {