feat: Add Kits + FurnaceSplitter plugin config modules

DB migrations 016 (kits_configs) and 019 (furnacesplitter_configs) applied.
Backend: NestJS modules with CRUD, apply-to-server, import-from-server.
Frontend: Pinia stores, Vue views with config editor, router + nav wiring.
Kits view: 3-tab editor (list/editor/settings), kit items with shortname/amount/skinId/container.
FurnaceSplitter view: per-furnace toggles, split count, fuel multiplier settings.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

frontend/src/components/layout/DashboardLayout.vue

@@ -31,6 +31,8 @@ import {
   Navigation2,
   Pickaxe,
   DoorOpen,
+  Gift,
+  Flame,
   Menu,
   X,
 } from 'lucide-vue-next'
@@ -52,6 +54,10 @@ const navItems = [
   { name: 'Teleport Config', path: '/teleport-config', icon: Navigation2, permission: 'teleport.view' },
   { name: 'Gather Rates', path: '/gather-manager', icon: Pickaxe, permission: 'gather.view' },
   { name: 'Auto Doors', path: '/autodoors', icon: DoorOpen, permission: 'autodoors.view' },
+  { name: 'Kits', path: '/kits', icon: Gift, permission: 'kits.view' },
+  { name: 'Furnace Splitter', path: '/furnace-splitter', icon: Flame, permission: 'furnacesplitter.view' },
+  { name: 'Better Chat', path: '/better-chat', icon: MessageSquare, permission: 'betterchat.view' },
+  { name: 'Timed Execute', path: '/timed-execute', icon: Clock, permission: 'timedexecute.view' },
   { name: 'Auto-Wiper', path: '/wipes', icon: RefreshCw, permission: 'wipes.view' },
   { name: 'Maps', path: '/maps', icon: Map, permission: 'maps.view' },
   { name: 'Chat Log', path: '/chat', icon: MessageSquare, permission: 'chat.view' },