Redesign login UI, add theme toggle, refactor user update

- Redesigned login page with two-panel layout and branding
- Added HexaDistro logo and theme toggle to sidebar/header
- Refactored user update: roles via update endpoint, removed assignRole API/controller
- Extended UpdateUserRequest for username, role, password changes
- UserService.UpdateAsync syncs changes with AuthHex, with rollback
- Stock balances client dedupes by itemId-locationId
- Middleware matcher excludes static assets from auth checks
- Improved localStorage clearing for user context
- Added lucide-react for icons
- Minor UI/code cleanups for consistency and UX

distribution_fe/app/(dashboard)/layout.tsx

@@ -1,6 +1,7 @@
 import { SidebarInset, SidebarProvider, SidebarTrigger } from '@/components/ui/sidebar'
 import { AppSidebar } from '@/components/layout/app-sidebar'
 import { BottomNav } from '@/components/layout/bottom-nav'
+import { ThemeToggle } from '@/components/layout/theme-toggle'
 
 export default function DashboardLayout({
   children,
@@ -13,6 +14,9 @@ export default function DashboardLayout({
       <SidebarInset>
         <header className="flex h-14 shrink-0 items-center gap-2 border-b border-border px-4">
           <SidebarTrigger className="-ml-1 hidden md:flex" />
+          <div className="ml-auto">
+            <ThemeToggle />
+          </div>
         </header>
         <main className="flex flex-1 flex-col gap-4 p-4 pb-20 md:pb-4">
           {children}