Add PageShell — collapsed sidebar strip on Dashboard and all admin pages

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

src/components/PageShell.tsx

@@ -0,0 +1,57 @@
+import { useState } from 'react'
+import { ChevronRight } from 'lucide-react'
+import { Sidebar } from './Sidebar'
+import type { User } from '../types'
+
+interface Props {
+  user: User
+  children: React.ReactNode
+  padding?: string
+}
+
+export function PageShell({ user, children, padding = '1.5rem 2rem' }: Props) {
+  const [menuOpen, setMenuOpen] = useState(false)
+
+  return (
+    <div style={{ display: 'flex', height: '100dvh' }}>
+
+      {/* Collapsed sidebar strip */}
+      <div style={{
+        width: 44, flexShrink: 0,
+        background: 'var(--navy)', borderRight: '1px solid var(--surface-2)',
+        display: 'flex', alignItems: 'center', justifyContent: 'center',
+        height: '100dvh', position: 'sticky', top: 0,
+      }}>
+        <button
+          onClick={() => setMenuOpen(true)}
+          title="Open menu"
+          style={{
+            background: 'none', border: 'none', cursor: 'pointer',
+            color: 'var(--text-muted)', padding: '0.5rem',
+            display: 'flex', alignItems: 'center', justifyContent: 'center',
+            borderRadius: 6,
+          }}
+        >
+          <ChevronRight size={18} strokeWidth={1.75} />
+        </button>
+      </div>
+
+      {/* Overlay sidebar + backdrop when open */}
+      {menuOpen && (
+        <>
+          <div
+            onClick={() => setMenuOpen(false)}
+            style={{ position: 'fixed', inset: 0, zIndex: 19, background: 'rgba(0,0,0,0.35)' }}
+          />
+          <div style={{ position: 'fixed', left: 0, top: 0, height: '100dvh', zIndex: 20 }}>
+            <Sidebar user={user} onCollapse={() => setMenuOpen(false)} />
+          </div>
+        </>
+      )}
+
+      <main style={{ flex: 1, overflowY: 'auto', padding }}>
+        {children}
+      </main>
+    </div>
+  )
+}