feat: Multi-User/Admin usermanagement + Galaxy Login/Settings + Task detail improvements

- Backend: NEW AdminController with user CRUD (GET/POST/DELETE /api/v1/admin/users)
- Backend: NEW GET /api/dashboard/tasks/{id} single task endpoint
- Backend: NEW POST /api/dashboard/tasks/{id}/activity comment endpoint
- Backend: IUserRepository + UserRepository extended with GetAllAsync, DeleteAsync
- Backend: Admin DTOs (AdminUserInfo, AdminCreateUserRequest, AdminUpdateRoleRequest)
- Frontend: NEW TaskDetailView.vue — URL-based (/tasks/:id) Galaxy-themed task detail
  with subtask create/edit/delete, activity with comments, property sidebar
- Frontend: LoginView.vue — полностью Galaxy theme redesign with GalaxyBackground,
  glass-morphism card, password toggle, consistent brand
- Frontend: SettingsView.vue — Galaxy theme redesign with glass cards,
  admin user management section (create/list users, visible only to owner role)
- Frontend: TaskBoardView.vue — added "Full View" link to URL-based detail page
- Frontend: Router — added /tasks/:id route for TaskDetailView
- Frontend: App.vue — added TaskDetail to standaloneViews whitelist
- Frontend: tasks store — stable

Auth: Admin creates accounts, users log in with existing /api/v1/auth/login.
Login/Settings deliver visible Galaxy-consistent design with nexus-tokens.css tokens.

backend/Services/TaskService.cs

@@ -1,4 +1,3 @@
-using System.Text.RegularExpressions;
 using Nexus.Api.Data;
 using Nexus.Api.DTOs;
 using Nexus.Api.Models;
@@ -350,74 +349,6 @@ public sealed class TaskService(
         return all.Where(e => e.TaskId == taskId).ToList();
     }
 
-    public async Task<int> ImportFromIrisTodoAsync(bool deleteAfterImport = false, CancellationToken ct = default)
-    {
-        var todoPath = "/mnt/workspace-iris/TODO.md";
-        if (!File.Exists(todoPath)) return 0;
-
-        var content = await File.ReadAllTextAsync(todoPath, ct);
-        var lines = content.Split('\n');
-
-        var imported = 0;
-        string? currentPriority = null;
-
-        // Parse sections and extract tasks with assignee info
-        // Pattern: ### N. Title 👤 Person
-        var taskPattern = new Regex(@"^###\s+\d+\.\s+(.+?)(?:\s+👤\s+(.+?))?$", RegexOptions.Compiled);
-        foreach (var line in lines)
-        {
-            var trimmed = line.Trim();
-
-            // Detect priority section
-            if (trimmed.StartsWith("## "))
-            {
-                var sectionLower = trimmed.ToLowerInvariant();
-                if (sectionLower.Contains("high")) currentPriority = "High";
-                else if (sectionLower.Contains("medium")) currentPriority = "Medium";
-                else if (sectionLower.Contains("low")) currentPriority = "Low";
-                else currentPriority = "Medium";
-                continue;
-            }
-
-            var match = taskPattern.Match(trimmed);
-            if (!match.Success) continue;
-
-            var title = match.Groups[1].Value.Trim();
-            var assigneeRaw = match.Groups[2].Success ? match.Groups[2].Value.Trim() : null;
-
-            // Resolve assignee: "Iris" → "iris", "Bao" → "bao", "Iris+Bao" → "iris"
-            string? assignedTo = null;
-            if (!string.IsNullOrWhiteSpace(assigneeRaw))
-            {
-                var lower = assigneeRaw.ToLowerInvariant();
-                if (lower.Contains("iris")) assignedTo = "iris";
-                else if (lower.Contains("bao")) assignedTo = "bao";
-            }
-
-            var task = new WorkTask
-            {
-                Title = title,
-                Source = "iris",
-                Priority = currentPriority ?? "Medium",
-                AssignedTo = assignedTo
-            };
-            await taskRepo.AddAsync(task, ct);
-            imported++;
-        }
-
-        if (deleteAfterImport)
-        {
-            File.Delete(todoPath);
-            await activityRepo.AddAsync(new ActivityEvent { Type = "task", Message = $"Imported {imported} tasks from TODO.md and deleted the file" }, ct);
-        }
-        else
-        {
-            await activityRepo.AddAsync(new ActivityEvent { Type = "task", Message = $"Imported {imported} tasks from TODO.md" }, ct);
-        }
-
-        return imported;
-    }
-
     private static DashboardTaskDto MapToDto(WorkTask t) => new(
         t.Id, t.Title, t.Detail, t.Source, t.State, t.Priority, t.AssignedTo,
         t.ParentTaskId, t.DueDate, t.CreatedAt, t.UpdatedAt);