fix: restore MapFallbackToFile-only WASM configuration (c960860 style)

Reverted to c960860's proven configuration:
- NO MapRazorComponents (pure static WASM delivery)
- MapFallbackToFile for admin/portal SPA routing
- UseStaticFiles("/admin") for path-based static file serving

Issue with blazor.boot.json:
- MapRazorComponents should auto-generate it, but doesn't in our setup
- c960860 also had no MapRazorComponents, suggesting static-only approach works
- SRI integrity check failures may be browser cache or other cause

Current approach (c960860):
- WASM files served as pure static assets ✅
- MapFallbackToFile routes SPA requests ✅
- Next: Direct browser testing to verify WASM renders

Co-Authored-By: Claude Haiku 4.5 <noreply@anthropic.com>

README.md

@@ -178,7 +178,10 @@ master 브랜치에 푸시하면 파이프라인이 다음 단계를 수행합
 | --- | --- | --- |
 | Public smoke | `E2E_BASE_URL=https://www.taxbaik.com/taxbaik npm run test:e2e:public-smoke` | `$env:E2E_BASE_URL="https://www.taxbaik.com/taxbaik"; npm run test:e2e:public-smoke` |
 | Admin smoke | `E2E_BASE_URL=https://www.taxbaik.com/taxbaik npm run test:e2e:admin-smoke` | `$env:E2E_BASE_URL="https://www.taxbaik.com/taxbaik"; npm run test:e2e:admin-smoke` |
-| Direct smoke script | `ROOT_URL="https://www.taxbaik.com/" ADMIN_URL="https://www.taxbaik.com/taxbaik/admin/login" bash ./scripts/taxbaik-smoke.sh` | `$env:ROOT_URL="https://www.taxbaik.com/"; $env:ADMIN_URL="https://www.taxbaik.com/taxbaik/admin/login"; bash ./scripts/taxbaik-smoke.sh` |
+
+직접 smoke 스크립트가 필요하면 이 한 줄만 쓰면 됩니다.
+
+`ROOT_URL="https://www.taxbaik.com/" ADMIN_URL="https://www.taxbaik.com/taxbaik/admin/login" bash ./scripts/taxbaik-smoke.sh`
 
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