fix(ai): I1+I3 — Redis TTL + openclaw_nemo 命名對齊

I1: ai_control.py 所有寫入 Redis 的 key 加入 30 天 TTL
    防止 ai:control:* keys 永久累積造成記憶體洩漏

I3: ai_rate_limiter.py "nvidia" key → "openclaw_nemo"
    對齊 Phase 24 AIProviderEnum，使 rate limit 正確作用

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

apps/api/src/services/ai_control.py

@@ -6,9 +6,9 @@ Telegram /ai 指令動態控制 AI Router 狀態
 - OPENCLAW_TG_USER_WHITELIST 白名單保護
 
 Redis Keys:
-  ai:control:use_router          "true"/"false" (覆蓋 USE_AI_ROUTER env)
-  ai:control:primary_provider    "openclaw_nemo"/"gemini"/"ollama"/"claude"
-  ai:control:disabled:<provider> "1" (TTL: 永久或手動清除)
+  ai:control:use_router          "true"/"false" (TTL: 30天)
+  ai:control:primary_provider    "openclaw_nemo"/"gemini"/"ollama"/"claude" (TTL: 30天)
+  ai:control:disabled:<provider> "1" (TTL: 30天)
 
 Usage:
   /ai status       — 顯示所有 Provider 狀態 + 當前路由模式
@@ -29,6 +29,9 @@ _AI_ROUTER_KEY = "ai:control:use_router"
 _PRIMARY_PROVIDER_KEY = "ai:control:primary_provider"
 _DISABLED_KEY_PREFIX = "ai:control:disabled:"
 
+# 2026-04-03 ogt: I1 防止記憶體洩漏 — 所有控制 key 統一 30 天 TTL
+_CONTROL_KEY_TTL = 30 * 24 * 3600  # 30 days
+
 VALID_PROVIDERS = {"openclaw_nemo", "gemini", "ollama", "claude", "nemotron"}
 
 
@@ -57,7 +60,7 @@ async def set_ai_router_enabled(enabled: bool) -> bool:
     """設定 AIRouter 啟用狀態到 Redis"""
     try:
         r = await _get_redis()
-        await r.set(_AI_ROUTER_KEY, "true" if enabled else "false")
+        await r.set(_AI_ROUTER_KEY, "true" if enabled else "false", ex=_CONTROL_KEY_TTL)
         logger.info("ai_control_router_set", enabled=enabled)
         return True
     except Exception as e:
@@ -83,7 +86,7 @@ async def set_primary_provider(provider: str) -> bool:
         return False
     try:
         r = await _get_redis()
-        await r.set(_PRIMARY_PROVIDER_KEY, provider)
+        await r.set(_PRIMARY_PROVIDER_KEY, provider, ex=_CONTROL_KEY_TTL)
         logger.info("ai_control_primary_set", provider=provider)
         return True
     except Exception as e:
@@ -119,7 +122,7 @@ async def set_provider_disabled(provider: str, disabled: bool) -> bool:
         r = await _get_redis()
         key = f"{_DISABLED_KEY_PREFIX}{provider}"
         if disabled:
-            await r.set(key, "1")
+            await r.set(key, "1", ex=_CONTROL_KEY_TTL)
         else:
             await r.delete(key)
         logger.info("ai_control_provider_set", provider=provider, disabled=disabled)