feat: add Docker node type, group rect border style, and categorized node type selector

- Fix DockerNode default icon: use Anchor instead of Package
- Add border_style option to Group Rectangle (solid/dashed/dotted/double/none)
- Group node type selector by category (Hardware, Virtualization, IoT, Generic)
- Add tests for border style feature

frontend/src/components/canvas/nodes/GroupRectNode.tsx

@@ -31,6 +31,7 @@ export function GroupRectNode({ id, data, selected }: NodeProps<Node<NodeData>>)
 
   const rc = data.custom_colors ?? {}
   const borderColor = rc.border ?? '#00d4ff'
+  const borderStyle = rc.border_style ?? 'solid'
   const backgroundColor = rc.background ?? 'rgba(0,212,255,0.05)'
   const textColor = rc.text_color ?? '#e6edf3'
   const fontFamily = FONT_FAMILIES[rc.font ?? 'inter'] ?? FONT_FAMILIES.inter
@@ -61,7 +62,7 @@ export function GroupRectNode({ id, data, selected }: NodeProps<Node<NodeData>>)
           justifyContent: posStyle.justifyContent,
           padding: 12,
           background: backgroundColor,
-          border: `${selected ? 2 : 1}px solid ${selected ? '#00d4ff' : borderColor}`,
+          border: `${selected ? 2 : 1}px ${selected ? 'solid' : borderStyle} ${selected ? '#00d4ff' : borderColor}`,
           borderRadius: 10,
           fontFamily,
           color: textColor,

frontend/src/components/canvas/nodes/index.tsx

@@ -1,7 +1,7 @@
 import { type NodeProps, type Node } from '@xyflow/react'
 import {
   Globe, Router, Network, Server, Layers, Box, Container,
-  HardDrive, Cpu, Wifi, Circle, Cctv, Printer, Monitor, PlugZap,
+  HardDrive, Cpu, Wifi, Circle, Cctv, Printer, Monitor, PlugZap, Anchor,
 } from 'lucide-react'
 import { BaseNode } from './BaseNode'
 import type { NodeData } from '@/types'
@@ -22,4 +22,5 @@ export const CameraNode   = (props: N) => <BaseNode {...props} icon={Cctv} />
 export const PrinterNode  = (props: N) => <BaseNode {...props} icon={Printer} />
 export const ComputerNode = (props: N) => <BaseNode {...props} icon={Monitor} />
 export const CplNode      = (props: N) => <BaseNode {...props} icon={PlugZap} />
+export const DockerNode   = (props: N) => <BaseNode {...props} icon={Anchor} />
 export const GenericNode  = (props: N) => <BaseNode {...props} icon={Circle} />

frontend/src/components/canvas/nodes/nodeTypes.ts

@@ -1,4 +1,4 @@
-import { IspNode, RouterNode, SwitchNode, ServerNode, VmNode, LxcNode, NasNode, IotNode, ApNode, CameraNode, PrinterNode, ComputerNode, CplNode, GenericNode } from './index'
+import { IspNode, RouterNode, SwitchNode, ServerNode, VmNode, LxcNode, NasNode, IotNode, ApNode, CameraNode, PrinterNode, ComputerNode, CplNode, DockerNode, GenericNode } from './index'
 import { ProxmoxGroupNode } from './ProxmoxGroupNode'
 import { GroupRectNode } from './GroupRectNode'
 
@@ -17,6 +17,7 @@ export const nodeTypes = {
   printer: PrinterNode,
   computer: ComputerNode,
   cpl: CplNode,
+  docker: DockerNode,
   generic: GenericNode,
   groupRect: GroupRectNode,
 }