T1/Phase 1: scaffold Vite SPA + Hono API + Bun worker

- apps/web: Vite + React 19 + TanStack Router/Query + shadcn/ui
   - apps/api: Hono + Bun on :3001 with /api/health, /api/auth/*, /mcp stubs
   - apps/worker: Bun worker stub, DB connection, graceful SIGTERM
   - apps/web-legacy/: old Next.js code moved aside (preserved for T2-T8 reference)
   - Dockerfiles: api (Bun), worker (Bun), spa (multi-stage Caddy)
   - Caddyfile: serves dist + reverse-proxies /api/* + /mcp to api
   - docker-compose.yml: 4-service target (api, spa, db, worker)
   - packages/db/src/client.ts: shared Drizzle client for api + worker
   - db/client.ts: root-level alias for convenience

   Parent: t_e1cbd87d -> t_24c9c3fd (T0)

apps/web-legacy/components/ui/separator.tsx

@@ -0,0 +1,26 @@
+'use client';
+
+import * as React from 'react';
+import * as SeparatorPrimitive from '@radix-ui/react-separator';
+
+import { cn } from '@/lib/utils';
+
+const Separator = React.forwardRef<
+  React.ComponentRef<typeof SeparatorPrimitive.Root>,
+  React.ComponentPropsWithoutRef<typeof SeparatorPrimitive.Root>
+>(({ className, orientation = 'horizontal', decorative = true, ...props }, ref) => (
+  <SeparatorPrimitive.Root
+    ref={ref}
+    decorative={decorative}
+    orientation={orientation}
+    className={cn(
+      'shrink-0 bg-border',
+      orientation === 'horizontal' ? 'h-[1px] w-full' : 'h-full w-[1px]',
+      className
+    )}
+    {...props}
+  />
+));
+Separator.displayName = SeparatorPrimitive.Root.displayName;
+
+export { Separator };