fix(ai): NVIDIA 加入 Rate Limiter 檢查

2026-03-30 ogt: 修復 AI 仲裁降級問題

問題: NVIDIA RPM=5 限制未在 fallback 檢查
修正: 加入 nvidia 到 rate_limiter 檢查清單

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

apps/api/src/services/openclaw.py

@@ -855,8 +855,9 @@ class OpenClawService:
             rate_limiter = get_ai_rate_limiter()
 
             for provider in settings.AI_FALLBACK_ORDER:
-                # Rate Limit 檢查 (gemini/claude 需檢查，ollama 不限)
-                if provider in ("gemini", "claude"):
+                # Rate Limit 檢查 (nvidia/gemini/claude 需檢查，ollama 不限)
+                # 2026-03-30 ogt: 加入 nvidia (RPM=5 限制)
+                if provider in ("nvidia", "gemini", "claude"):
                     allowed, reason = await rate_limiter.check_and_increment(provider)
                     if not allowed:
                         logger.warning(