feat: Add Wild Central web app (Central-only UI)

Extract Central pages from the wild-cloud web app into a standalone
React app for Wild Central. Includes:

- Central overview, DNS, DHCP, Firewall, VPN, Ingress, CrowdSec pages
- Simplified sidebar with Central-only navigation
- Branding updated to "Wild Central"
- All Cloud-specific pages, components, hooks, and API services removed
- TypeScript type-check and production build pass

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

web/src/components/AppSidebar.tsx

@@ -0,0 +1,134 @@
+import { NavLink } from 'react-router';
+import { Sun, Moon, Monitor, Shield, Lock, Network, ShieldAlert, Router, Cloud, Wifi, Server } from 'lucide-react';
+import {
+  Sidebar,
+  SidebarContent,
+  SidebarFooter,
+  SidebarGroup,
+  SidebarGroupContent,
+  SidebarGroupLabel,
+  SidebarHeader,
+  SidebarMenu,
+  SidebarMenuButton,
+  SidebarMenuItem,
+  SidebarRail,
+  useSidebar,
+} from './ui/sidebar';
+import { useTheme } from '../contexts/ThemeContext';
+
+export function AppSidebar() {
+  const { theme, setTheme } = useTheme();
+  const { state } = useSidebar();
+
+  const cycleTheme = () => {
+    if (theme === 'light') {
+      setTheme('dark');
+    } else if (theme === 'dark') {
+      setTheme('system');
+    } else {
+      setTheme('light');
+    }
+  };
+
+  const getThemeIcon = () => {
+    switch (theme) {
+      case 'light':
+        return <Sun className="h-4 w-4" />;
+      case 'dark':
+        return <Moon className="h-4 w-4" />;
+      default:
+        return <Monitor className="h-4 w-4" />;
+    }
+  };
+
+  const getThemeLabel = () => {
+    switch (theme) {
+      case 'light':
+        return 'Light mode';
+      case 'dark':
+        return 'Dark mode';
+      default:
+        return 'System theme';
+    }
+  };
+
+  const centralItems = [
+    { to: '/central', icon: Server, label: 'Overview', end: true },
+    { to: '/central/cloudflare', icon: Cloud, label: 'Cloudflare' },
+    { to: '/central/dns', icon: Router, label: 'DNS' },
+    { to: '/central/ingress', icon: Network, label: 'Ingress Proxy' },
+    { to: '/central/firewall', icon: Shield, label: 'Firewall' },
+    { to: '/central/vpn', icon: Lock, label: 'VPN' },
+    { to: '/central/crowdsec', icon: ShieldAlert, label: 'CrowdSec' },
+    { to: '/central/dhcp', icon: Wifi, label: 'DHCP' },
+  ];
+
+  return (
+    <Sidebar variant="sidebar" collapsible="icon">
+      <SidebarHeader>
+        <div className="flex items-center justify-center pb-2">
+          <div className="p-1 bg-primary/10 rounded-lg">
+            <Server className="h-6 w-6 text-primary" />
+          </div>
+          <div className="overflow-hidden transition-all duration-200 ease-linear ml-2 max-w-[200px] opacity-100 group-data-[collapsible=icon]:ml-0 group-data-[collapsible=icon]:max-w-0 group-data-[collapsible=icon]:opacity-0">
+            <h2 className="text-lg font-bold text-foreground whitespace-nowrap">Wild Central</h2>
+          </div>
+        </div>
+      </SidebarHeader>
+
+      <SidebarContent>
+        {state === 'collapsed' ? (
+          <SidebarMenu>
+            {centralItems.map(({ to, icon: Icon, label, end }) => (
+              <SidebarMenuItem key={to}>
+                <NavLink to={to} end={end}>
+                  {({ isActive }) => (
+                    <SidebarMenuButton isActive={isActive} tooltip={label}>
+                      <Icon className="h-4 w-4" />
+                      <span>{label}</span>
+                    </SidebarMenuButton>
+                  )}
+                </NavLink>
+              </SidebarMenuItem>
+            ))}
+          </SidebarMenu>
+        ) : (
+          <SidebarGroup>
+            <SidebarGroupLabel>Central</SidebarGroupLabel>
+            <SidebarGroupContent>
+              <SidebarMenu>
+                {centralItems.map(({ to, icon: Icon, label, end }) => (
+                  <SidebarMenuItem key={to}>
+                    <NavLink to={to} end={end}>
+                      {({ isActive }) => (
+                        <SidebarMenuButton isActive={isActive}>
+                          <Icon className="h-4 w-4" />
+                          <span className="truncate">{label}</span>
+                        </SidebarMenuButton>
+                      )}
+                    </NavLink>
+                  </SidebarMenuItem>
+                ))}
+              </SidebarMenu>
+            </SidebarGroupContent>
+          </SidebarGroup>
+        )}
+      </SidebarContent>
+
+      <SidebarFooter>
+        <SidebarMenu>
+          <SidebarMenuItem>
+            <SidebarMenuButton
+              onClick={cycleTheme}
+              tooltip={`Current: ${getThemeLabel()}. Click to cycle themes.`}
+            >
+              {getThemeIcon()}
+              <span>{getThemeLabel()}</span>
+            </SidebarMenuButton>
+          </SidebarMenuItem>
+        </SidebarMenu>
+      </SidebarFooter>
+      <SidebarRail/>
+    </Sidebar>
+  );
+}