Add laptop and mobile node types

Personal computing devices (laptops, phones, tablets) currently collapse
into the generic icon because the type vocabulary has no entries for
them. This adds two new NodeTypes with Lucide icons:

- laptop  -> Laptop icon (reuses the computer accent color per theme)
- mobile  -> Smartphone icon (new pink accent #ec4899 across themes)

Touches:
- types/index.ts                    NodeType union + NODE_TYPE_LABELS
- utils/nodeIcons.ts                Lucide import + ICON_REGISTRY +
                                    NODE_TYPE_DEFAULT_ICONS
- utils/themes.ts                   nodeAccents in all 6 themes
- canvas/nodes/index.tsx            LaptopNode + MobileNode wrappers
- canvas/nodes/nodeTypes.ts         register in react-flow nodeTypes
- modals/NodeModal.tsx              new "Personal" type group
- modals/CustomStyleModal.tsx       expose new types in style editor
- types/__tests__/types.test.ts     enumerate new types
- utils/__tests__/themes.test.ts    enumerate new types

Backwards-compatible: existing nodes typed as 'generic', 'server', etc.
keep rendering exactly as before. No data migration required.

frontend/src/components/modals/CustomStyleModal.tsx

@@ -2,7 +2,7 @@ import { useState, useCallback } from 'react'
 import { toast } from 'sonner'
 import {
   Globe, Router, Network, Server, Layers, Box, Container, HardDrive,
-  Cpu, Wifi, Camera, Printer, Monitor, PlugZap, Anchor, Package, Circle, Flame,
+  Cpu, Wifi, Camera, Printer, Monitor, Laptop, Smartphone, PlugZap, Anchor, Package, Circle, Flame,
   Radio, Zap, Lightbulb,
   type LucideIcon,
 } from 'lucide-react'
@@ -21,7 +21,7 @@ import { NODE_TYPE_LABELS, EDGE_TYPE_LABELS } from '@/types'
 
 const EDITABLE_NODE_TYPES: NodeType[] = [
   'isp', 'router', 'firewall', 'switch', 'server', 'proxmox', 'vm', 'lxc', 'nas',
-  'iot', 'ap', 'camera', 'printer', 'computer', 'cpl', 'docker_host',
+  'iot', 'ap', 'camera', 'printer', 'computer', 'laptop', 'mobile', 'cpl', 'docker_host',
   'docker_container', 'zigbee_coordinator', 'zigbee_router', 'zigbee_enddevice',
   'generic',
 ]
@@ -31,7 +31,7 @@ const EDITABLE_EDGE_TYPES: EdgeType[] = ['ethernet', 'wifi', 'iot', 'vlan', 'vir
 const NODE_ICONS: Record<string, LucideIcon> = {
   isp: Globe, router: Router, firewall: Flame, switch: Network, server: Server, proxmox: Layers,
   vm: Box, lxc: Container, nas: HardDrive, iot: Cpu, ap: Wifi,
-  camera: Camera, printer: Printer, computer: Monitor, cpl: PlugZap,
+  camera: Camera, printer: Printer, computer: Monitor, laptop: Laptop, mobile: Smartphone, cpl: PlugZap,
   docker_host: Anchor, docker_container: Package,
   zigbee_coordinator: Radio, zigbee_router: Zap, zigbee_enddevice: Lightbulb,
   generic: Circle,

frontend/src/components/modals/NodeModal.tsx

@@ -18,7 +18,8 @@ const NODE_TYPE_GROUPS: { label: string; types: NodeType[] }[] = [
   { label: 'Virtualization', types: ['proxmox', 'vm', 'lxc', 'docker_host', 'docker_container'] },
   { label: 'IoT',            types: ['iot', 'camera', 'cpl'] },
   { label: 'Zigbee',         types: ['zigbee_coordinator', 'zigbee_router', 'zigbee_enddevice'] },
-  { label: 'Generic',        types: ['computer', 'generic', 'groupRect'] },
+  { label: 'Personal',       types: ['computer', 'laptop', 'mobile'] },
+  { label: 'Generic',        types: ['generic', 'groupRect'] },
 ]
 
 const CHECK_METHODS: CheckMethod[] = ['none', 'ping', 'http', 'https', 'tcp', 'ssh', 'prometheus', 'health']