Implement Owner Panel features and maintenance mode handling

- Introduced the Owner Panel with new routes and UI components for managing guilds, user blacklists, feature flags, and bot presence.
- Added maintenance mode functionality to prevent non-owner users from executing commands during maintenance periods.
- Enhanced localization with new keys for Owner Panel features in both English and German.
- Updated job processing to include a presence refresh job, ensuring the bot's status is regularly updated.
- Improved environment configuration to support owner user IDs for access control.

apps/webui/src/components/layout/dashboard-shell.tsx

@@ -9,17 +9,25 @@ interface DashboardShellProps {
   currentGuild: DashboardGuild;
   otherGuilds: DashboardGuild[];
   user: SessionUser;
+  showOwnerLink?: boolean;
   children: ReactNode;
 }
 
-export function DashboardShell({ guildId, currentGuild, otherGuilds, user, children }: DashboardShellProps) {
+export function DashboardShell({
+  guildId,
+  currentGuild,
+  otherGuilds,
+  user,
+  showOwnerLink = false,
+  children
+}: DashboardShellProps) {
   return (
     <div className="flex min-h-screen">
       <Sidebar guildId={guildId} />
       <div className="flex flex-1 flex-col">
         <header className="flex h-14 items-center justify-between border-b border-border px-6">
           <ServerSwitcher currentGuild={currentGuild} otherGuilds={otherGuilds} />
-          <UserMenu user={user} />
+          <UserMenu user={user} showOwnerLink={showOwnerLink} />
         </header>
         <main className="flex-1 px-6 py-8">
           <div className="mx-auto w-full max-w-[1200px]">{children}</div>

apps/webui/src/components/layout/user-menu.tsx

@@ -1,7 +1,7 @@
 'use client';
 
 import type { SessionUser } from '@nexumi/shared';
-import { LogOut, Moon, Sun } from 'lucide-react';
+import { LogOut, Moon, Shield, Sun } from 'lucide-react';
 import { useTheme } from 'next-themes';
 import { useRouter } from 'next/navigation';
 import { useState } from 'react';
@@ -26,7 +26,7 @@ function initials(user: SessionUser): string {
   return name.slice(0, 2).toUpperCase();
 }
 
-export function UserMenu({ user }: { user: SessionUser }) {
+export function UserMenu({ user, showOwnerLink = false }: { user: SessionUser; showOwnerLink?: boolean }) {
   const t = useTranslations();
   const { theme, setTheme } = useTheme();
   const router = useRouter();
@@ -58,6 +58,19 @@ export function UserMenu({ user }: { user: SessionUser }) {
       <DropdownMenuContent align="end" className="w-56">
         <DropdownMenuLabel className="truncate">{user.globalName ?? user.username}</DropdownMenuLabel>
         <DropdownMenuSeparator />
+        {showOwnerLink ? (
+          <>
+            <DropdownMenuItem
+              onClick={() => {
+                router.push('/owner');
+              }}
+            >
+              <Shield className="size-4" />
+              {t('userMenu.ownerPanel')}
+            </DropdownMenuItem>
+            <DropdownMenuSeparator />
+          </>
+        ) : null}
         <DropdownMenuItem onClick={() => setTheme(theme === 'dark' ? 'light' : 'dark')}>
           {theme === 'dark' ? <Sun className="size-4" /> : <Moon className="size-4" />}
           {theme === 'dark' ? t('userMenu.themeLight') : t('userMenu.themeDark')}