feat(01-foundation-01): register branding package in root vitest config

- Add "packages/branding" to root vitest.config.ts projects array
- Enables pnpm vitest run --project "@paperclipai/branding" from repo root

vitest.config.ts

@@ -9,6 +9,7 @@ export default defineConfig({
       "server",
       "ui",
       "cli",
+      "packages/branding",
     ],
   },
 });