Add USB, Notifications, Network plugins and reusable EmployeeSearch component

New Plugins:
- USB plugin: Device checkout/checkin with employee lookup, checkout history
- Notifications plugin: Announcements with types, scheduling, shopfloor display
- Network plugin: Network device management with subnets and VLANs
- Equipment and Computers plugins: Asset type separation

Frontend:
- EmployeeSearch component: Reusable employee lookup with autocomplete
- USB views: List, detail, checkout/checkin modals
- Notifications views: List, form with recognition mode
- Network views: Device list, detail, form
- Calendar view with FullCalendar integration
- Shopfloor and TV dashboard views
- Reports index page
- Map editor for asset positioning
- Light/dark mode fixes for map tooltips

Backend:
- Employee search API with external lookup service
- Collector API for PowerShell data collection
- Reports API endpoints
- Slides API for TV dashboard
- Fixed AppVersion model (removed BaseModel inheritance)
- Added checkout_name column to usbcheckouts table

Styling:
- Unified detail page styles
- Improved pagination (page numbers instead of prev/next)
- Dark/light mode theme improvements

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

frontend/src/views/settings/SettingsIndex.vue

@@ -50,6 +50,18 @@
         <h3>Business Units</h3>
         <p>Manage organizational units</p>
       </router-link>
+
+      <router-link to="/settings/vlans" class="settings-card">
+        <div class="card-icon">🌐</div>
+        <h3>VLANs</h3>
+        <p>Manage virtual LANs</p>
+      </router-link>
+
+      <router-link to="/settings/subnets" class="settings-card">
+        <div class="card-icon">🔗</div>
+        <h3>Subnets</h3>
+        <p>Manage IP subnets and DHCP</p>
+      </router-link>
     </div>
   </div>
 </template>
@@ -71,8 +83,8 @@
 .settings-card {
   display: block;
   padding: 1.5rem;
-  background: white;
-  border: 1px solid #e0e0e0;
+  background: var(--bg-card);
+  border: 1px solid var(--border);
   border-radius: 8px;
   text-decoration: none;
   color: inherit;
@@ -80,8 +92,8 @@
 }
 
 .settings-card:hover {
-  border-color: #1976d2;
-  box-shadow: 0 2px 8px rgba(0,0,0,0.1);
+  border-color: var(--primary);
+  box-shadow: 0 2px 8px rgba(0,0,0,0.15);
 }
 
 .card-icon {
@@ -91,12 +103,12 @@
 
 .settings-card h3 {
   margin: 0 0 0.5rem 0;
-  color: #333;
+  color: var(--text);
 }
 
 .settings-card p {
   margin: 0;
-  color: #666;
+  color: var(--text-light);
   font-size: 0.9rem;
 }
 </style>