fix: reject REDIS_CACHE_TTL<=0 (kill implicit never-expire)

main.py

@@ -84,13 +84,14 @@ def _build_adapters(settings: InfraSettings, embed_cfg: dict) -> _Adapters:
 
     cache = None
     if settings.redis_url:
+        from adapters.redis_cache import RedisResponseCache, _resolve_cache_ttl
+
+        # 配置校验 fail-loud（不属于 Redis 连接故障，不得被下方降级 except 吞掉）
+        ttl_s = _resolve_cache_ttl(settings.redis_cache_ttl)
         try:
             import redis.asyncio as aioredis
 
-            from adapters.redis_cache import RedisResponseCache
-
             redis_client = aioredis.from_url(settings.redis_url, decode_responses=True)
-            ttl_s = settings.redis_cache_ttl if settings.redis_cache_ttl > 0 else None
             cache = RedisResponseCache(redis=redis_client, ttl_s=ttl_s)
         except Exception:
             logger.warning("Redis 缓存不可用，降级为无缓存模式")