[CLAUDE] FE-Admin: redesign Phase 1 — density-first design system (NAMGROUP-ref, giữ brand)

Tham khảo NAMGROUP density conventions, GIỮ brand #1F7DC1 + Be Vietnam Pro.
- index.css: density heading ladder (semibold, drop font-bold) + .label-eyebrow util
- 6 UI primitives (Button/Input/Label/Select/Textarea/Dialog): text-xs font-semibold, py-1.5 ≤36px, rounded-lg, brand focus-ring
- 6 shell (DataTable sticky-thead+RowActions/Layout brand-rail/TopBar/PageHeader/PhaseBadge/EmptyState)
- DashboardPage flagship: KPI cards + brand-tinted icon chips + uppercase labels

Visual-only — functionality unchanged (Button variant/size keys stable 51 call-sites, props/forwardRef intact). build 0 TS err. reviewer PASS 0 blocker (2 minor slate-400 hint a11y defer). fe-admin only (fe-user mirror = Phase 3). Dashboard live-visual blocked by dev auth-rig → xem live sau deploy.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

fe-admin/src/components/TopBar.tsx

@@ -32,7 +32,7 @@ function UserMenu() {
         onClick={() => setOpen(o => !o)}
         className="flex items-center gap-2 rounded-md px-2 py-1.5 text-sm transition hover:bg-slate-100"
       >
-        <span className="flex h-7 w-7 items-center justify-center rounded-full bg-brand-100 text-xs font-bold text-brand-700">
+        <span className="flex h-7 w-7 items-center justify-center rounded-full bg-brand-100 text-[11px] font-semibold text-brand-700">
           {initials}
         </span>
         <span className="hidden max-w-32 truncate text-slate-700 md:inline">{user?.fullName ?? user?.email}</span>