Fix API paths and make hotel name configurable

- /api/notices → /notices/api/notices to match nginx location block
  (was returning portal index.html causing JSON parse error)
- Add VITE_HOTEL_NAME build arg, remove hardcoded hotel name
- Add vite-env.d.ts for TypeScript import.meta.env support

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

frontend/src/components/AuthGate.tsx

@@ -85,7 +85,7 @@ export function AuthGate({ children }: Props) {
             Noticeboard
           </h1>
           <p style={{ color: 'var(--text-muted)', fontSize: '0.875rem', marginBottom: '1.5rem' }}>
-            Hotel Number Four
+            {import.meta.env.VITE_HOTEL_NAME}
           </p>
           <form onSubmit={login} style={{ display: 'flex', flexDirection: 'column', gap: '0.75rem' }}>
             <input

frontend/src/components/NoticeBoard.tsx

@@ -29,19 +29,19 @@ export function NoticeBoard({ user }: { user: User }) {
 
   useEffect(() => {
     const params = category !== 'all' ? `?category=${category}` : ''
-    fetch(`/api/notices${params}`, { credentials: 'include' })
+    fetch(`/notices/api/notices${params}`, { credentials: 'include' })
       .then(r => r.json())
       .then(setNotices)
   }, [category, forceRefresh])
 
   async function togglePin(id: number) {
-    await fetch(`/api/notices/${id}/pin`, { method: 'PATCH', credentials: 'include' })
+    await fetch(`/notices/api/notices/${id}/pin`, { method: 'PATCH', credentials: 'include' })
     forceRefresh()
   }
 
   async function deleteNotice(id: number) {
     if (!confirm('Delete this notice?')) return
-    await fetch(`/api/notices/${id}`, { method: 'DELETE', credentials: 'include' })
+    await fetch(`/notices/api/notices/${id}`, { method: 'DELETE', credentials: 'include' })
     forceRefresh()
   }
 
@@ -155,7 +155,7 @@ function PostForm({ onPosted }: { onPosted: () => void }) {
     setSubmitting(true)
     setError('')
     try {
-      const res = await fetch('/api/notices', {
+      const res = await fetch('/notices/api/notices', {
         method: 'POST',
         credentials: 'include',
         headers: { 'Content-Type': 'application/json' },

frontend/src/vite-env.d.ts

@@ -0,0 +1,9 @@
+/// <reference types="vite/client" />
+
+interface ImportMetaEnv {
+  readonly VITE_HOTEL_NAME: string
+}
+
+interface ImportMeta {
+  readonly env: ImportMetaEnv
+}