feat: add single-port reverse proxy deployment support

apps/web/src/components/app-shell.tsx

@@ -38,6 +38,7 @@ export function AppShell({ children }: { children: React.ReactNode }) {
   const username = useSessionStore((state) => state.username)
   const clearSession = useSessionStore((state) => state.clearSession)
   const fullPlayerOpen = usePlayerStore((state) => state.fullPlayerOpen)
+  const currentOrigin = typeof window !== 'undefined' ? window.location.origin : ''
   const [settingsOpen, setSettingsOpen] = useState(false)
   const [userMenuOpen, setUserMenuOpen] = useState(false)
   const [paletteOpen, setPaletteOpen] = useState(false)
@@ -87,7 +88,7 @@ export function AppShell({ children }: { children: React.ReactNode }) {
               <div className="absolute right-0 top-10 z-30 w-64 overflow-hidden rounded-xl border border-[#24314f] bg-[#0d1528] shadow-2xl">
                 <div className="border-b border-[#24314f] px-4 py-3">
                   <div className="text-xl font-semibold text-white">{username ?? 'demo'}</div>
-                  <div className="mt-1 text-sm text-slate-400">https://music.daemonlord.ru</div>
+                  <div className="mt-1 text-sm text-slate-400">{currentOrigin || 'https://music.example.com'}</div>
                 </div>
                 <button className="flex w-full items-center justify-between px-4 py-3 text-left text-sm text-slate-100 hover:bg-[#18233a]" type="button">
                   Сочетания клавиш

apps/web/src/lib/api.ts

@@ -79,7 +79,7 @@ export type PlaylistDetail = PlaylistSummary & {
   tracks: Track[]
 }
 
-const API_BASE = import.meta.env.VITE_API_BASE ?? 'http://localhost:4040'
+const API_BASE = import.meta.env.VITE_API_BASE ?? ''
 
 async function request<T>(path: string, init?: RequestInit): Promise<T> {
   const token = useSessionStore.getState().token