feat(shell): 시안B 슬림 아이콘 레일 — 사이드바 접힘=54px 글로벌 네비(숨김 대신)

frontend/src/lib/components/SlimRail.svelte

@@ -0,0 +1,33 @@
+<script>
+  // 시안 B — 글로벌 네비 슬림 아이콘 레일 (분류 사이드바 접힘 상태). 앱 토큰 사용.
+  import { page } from '$app/stores';
+  import { Home, FolderTree, Newspaper, StickyNote, Hash, GraduationCap, MessageCircle, Inbox, CalendarCheck } from 'lucide-svelte';
+
+  const items = [
+    { href: '/', icon: Home, label: '홈', exact: true },
+    { href: '/library', icon: FolderTree, label: '문서' },
+    { href: '/news', icon: Newspaper, label: '뉴스' },
+    { href: '/memos', icon: StickyNote, label: '메모' },
+    { href: '/clause', icon: Hash, label: '절' },
+    { href: '/events', icon: CalendarCheck, label: '일정' },
+    { href: '/study', icon: GraduationCap, label: '공부' },
+    { href: '/chat', icon: MessageCircle, label: '이드' },
+    { href: '/inbox', icon: Inbox, label: '편지함' },
+  ];
+  let path = $derived($page.url.pathname);
+  const active = (it) => (it.exact ? path === it.href : path.startsWith(it.href));
+</script>
+
+<nav class="flex flex-col items-center gap-1 py-2 h-full overflow-y-auto bg-sidebar">
+  {#each items as it (it.href)}
+    {@const Icon = it.icon}
+    <a
+      href={it.href}
+      title={it.label}
+      class="flex flex-col items-center justify-center gap-0.5 w-12 h-[46px] rounded-lg text-dim hover:bg-surface-hover hover:text-accent transition-colors {active(it) ? 'bg-surface-active text-accent font-semibold' : ''}"
+    >
+      <Icon size={17} strokeWidth={1.75} />
+      <span class="text-[8.5px] leading-none tracking-tight">{it.label}</span>
+    </a>
+  {/each}
+</nav>

frontend/src/routes/+layout.svelte

@@ -11,6 +11,7 @@
   import { queueOverview } from '$lib/stores/queueOverview';
   import { MACHINE_STATE_LABEL, machineChipClass } from '$lib/utils/queueDisplay';
   import Sidebar from '$lib/components/Sidebar.svelte';
+  import SlimRail from '$lib/components/SlimRail.svelte';
   import SystemStatusDot from '$lib/components/SystemStatusDot.svelte';
   import QueueDrawer from '$lib/components/QueueDrawer.svelte';
   import QuickMemoButton from '$lib/components/QuickMemoButton.svelte';
@@ -198,8 +199,8 @@
       <!-- 메인: 데스크탑 상시 사이드바 + 콘텐츠 -->
       <div class="flex-1 min-h-0 flex">
         {#if showSidebar}
-          <aside class="hidden lg:block shrink-0 overflow-hidden transition-[width] duration-200 ease-out {sidebarCollapsed ? 'w-0 border-r-0' : 'w-sidebar border-r border-default'}">
-            <Sidebar />
+          <aside class="hidden lg:block shrink-0 overflow-hidden transition-[width] duration-200 ease-out {sidebarCollapsed ? 'w-14 border-r border-default' : 'w-sidebar border-r border-default'}">
+            {#if sidebarCollapsed}<SlimRail />{:else}<Sidebar />{/if}
           </aside>
         {/if}
         <main class="flex-1 min-w-0 overflow-auto">