feat: add hide IP toggle in sidebar

- Add hideIp / toggleHideIp to canvasStore (UI-only, not persisted)
- Add maskIp util: 192.168.1.115 → 192.168.XX.XX (non-IPv4 passthrough)
- BaseNode reads hideIp from store and masks last two octets when active
- Sidebar shows Eye/EyeOff toggle below Scan Network, highlights when active

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

@@ -6,6 +6,8 @@ import { resolveNodeColors } from '@/utils/nodeColors'
 import { resolveNodeIcon } from '@/utils/nodeIcons'
 import { useThemeStore } from '@/stores/themeStore'
 import { THEMES } from '@/utils/themes'
+import { useCanvasStore } from '@/stores/canvasStore'
+import { maskIp } from '@/utils/maskIp'
 
 interface BaseNodeProps extends NodeProps<Node<NodeData>> {
   icon: LucideIcon
@@ -13,6 +15,7 @@ interface BaseNodeProps extends NodeProps<Node<NodeData>> {
 
 export function BaseNode({ data, selected, icon: typeIcon }: BaseNodeProps) {
   const activeTheme = useThemeStore((s) => s.activeTheme)
+  const hideIp = useCanvasStore((s) => s.hideIp)
   const theme = THEMES[activeTheme]
 
   const resolvedIcon = resolveNodeIcon(typeIcon, data.custom_icon)
@@ -70,7 +73,7 @@ export function BaseNode({ data, selected, icon: typeIcon }: BaseNodeProps) {
             style={{ color: theme.colors.nodeSubtextColor }}
             title={data.ip}
           >
-            {data.ip}
+            {hideIp ? maskIp(data.ip) : data.ip}
           </div>
         )}
       </div>

frontend/src/components/panels/Sidebar.tsx

@@ -1,5 +1,5 @@
 import { useState, useCallback, useEffect, useRef } from 'react'
-import { Plus, Save, ScanLine, ChevronLeft, ChevronRight, LayoutDashboard, Clock, EyeOff, Trash2, RefreshCw, Loader2, Square } from 'lucide-react'
+import { Plus, Save, ScanLine, ChevronLeft, ChevronRight, LayoutDashboard, Clock, EyeOff, Trash2, RefreshCw, Loader2, Square, Eye } from 'lucide-react'
 import { Logo } from '@/components/ui/Logo'
 import { Tooltip, TooltipContent, TooltipTrigger } from '@/components/ui/tooltip'
 import { useCanvasStore } from '@/stores/canvasStore'
@@ -40,7 +40,7 @@ interface SidebarProps {
 export function Sidebar({ onAddNode, onAddGroupRect, onScan, onSave, onNodeApproved }: SidebarProps) {
   const [collapsed, setCollapsed] = useState(false)
   const [activeView, setActiveView] = useState<SidebarView>('canvas')
-  const { nodes, hasUnsavedChanges } = useCanvasStore()
+  const { nodes, hasUnsavedChanges, hideIp, toggleHideIp } = useCanvasStore()
 
   const networkNodes = nodes.filter((n) => n.data.type !== 'groupRect')
   const onlineCount = networkNodes.filter((n) => n.data.status === 'online').length
@@ -126,6 +126,13 @@ export function Sidebar({ onAddNode, onAddGroupRect, onScan, onSave, onNodeAppro
         <SidebarItem icon={Plus} label="Add Node" collapsed={collapsed} onClick={onAddNode} />
         <SidebarItem icon={Square} label="Add Rectangle" collapsed={collapsed} onClick={onAddGroupRect} />
         {!STANDALONE && <SidebarItem icon={ScanLine} label="Scan Network" collapsed={collapsed} onClick={handleScan} />}
+        <SidebarItem
+          icon={hideIp ? EyeOff : Eye}
+          label={hideIp ? 'Show IPs' : 'Hide IPs'}
+          collapsed={collapsed}
+          onClick={toggleHideIp}
+          active={hideIp}
+        />
         <SidebarItem
           icon={Save}
           label="Save Canvas"