* fix: correct non-standard 'yml' tag to 'yaml' in RedisOpts
* fix: apply MaxActive config to Redis PoolSize
* fix: clarify config semantics, enhance timeout & pool options, and maintain backward compatibility
* test: update unit test for redis
* refactor: apply suggestions from code review
* test: add comprehensive coverage for redis
* refactor: resolve funlen linter errors in redis unit tests
* refactor: remove empty else-if branch in NewRedis function
