fix[installer](templates): aligned gateway template with new style

[AlexSanchez-bit]

No description provided.

[github-actions]

🛑 AI review — Sensitive area, extra care recommended

This PR touches critical paths or introduces changes the model cannot judge with sufficient confidence. Review carefully before merging.

🛑 architecture (gemini-3-flash-lite) — high/critical — please review

Summary: Installer template modification detected; touches critical installer path.

• high installer/templates/nginx.go:1 — Changes to the installer template files touch critical installer code paths which are classified as Tier 3.

✅ bugs (gemini-3-flash-lite) — clean

Summary: Updated Nginx maintenance page template with improved modern design and dark mode support.

No findings.

✅ security (gemini-3-flash-lite) — clean

Summary: Updated Nginx maintenance page template HTML/CSS styling with no security vulnerabilities or data leaks.

No findings.

🔴 go-deps — pending updates

🔍 Discovered 30 Go projects

📦 Dependencies with updates available:

  📁 ./plugins/stats:
     - github.com/threatwinds/go-sdk: v1.1.27-0.20260811073440-251cb9d842cd → v1.1.28

  📁 ./plugins/feeds:
     - github.com/threatwinds/go-sdk: v1.1.27-0.20260811073440-251cb9d842cd → v1.1.28

  📁 ./plugins/aws:
     - github.com/threatwinds/go-sdk: v1.1.27-0.20260811073440-251cb9d842cd → v1.1.28

  📁 ./plugins/rule-flood-guard:
     - github.com/threatwinds/go-sdk: v1.1.27-0.20260811073440-251cb9d842cd → v1.1.28

  📁 ./plugins/alerts:
     - github.com/threatwinds/go-sdk: v1.1.27-0.20260811073440-251cb9d842cd → v1.1.28

  📁 ./plugins/events:
     - github.com/threatwinds/go-sdk: v1.1.27-0.20260811073440-251cb9d842cd → v1.1.28

  📁 ./backend:
     - github.com/threatwinds/go-sdk: v1.1.27-0.20260811073440-251cb9d842cd → v1.1.28

❌ Please update dependencies before merging.