Replace old team system with work teams (equipos de trabajo)

- New migration 003_teams.sql: teams, team_user, team_server tables
- New Team model with CRUD, members, and server assignment
- New TeamController with full team management
- New views: teams/index, teams/create, teams/show
- Server model: getUserRole and getAccessibleServerIds now include team-based access
- Sidebar: Teams link under Administration (admin+ only)
- Routes: old /team routes removed, new /teams routes added
- Removed old ServerController team methods and views
- Fixed sidebar empty accessible IDs returning all servers
- Fixed dashboard and API to show empty when no accessible servers

views/layouts/main.php

@@ -39,15 +39,15 @@
                             <div class="nav-submenu-loading"><i class="fas fa-spinner fa-spin"></i></div>
                         </div>
                     </li>
-                    <li class="nav-item">
-                        <a href="/team" class="nav-link <?= str_starts_with($_SERVER['REQUEST_URI'] ?? '', '/team') ? 'active' : '' ?>">
-                            <i class="fas fa-users-cog"></i>
-                            <span>Team</span>
-                        </a>
-                    </li>
                     <li class="nav-divider"></li>
                     <li class="nav-section">Administration</li>
                     <?php if (in_array($_SESSION['user_role'] ?? '', ['super_admin', 'admin'])): ?>
+                    <li class="nav-item">
+                        <a href="/teams" class="nav-link <?= str_starts_with($_SERVER['REQUEST_URI'] ?? '', '/teams') ? 'active' : '' ?>">
+                            <i class="fas fa-users-cog"></i>
+                            <span>Teams</span>
+                        </a>
+                    </li>
                     <li class="nav-item">
                         <a href="/admin/users" class="nav-link <?= str_starts_with($_SERVER['REQUEST_URI'] ?? '', '/admin/users') ? 'active' : '' ?>">
                             <i class="fas fa-users"></i>