What are the features and specifications of the TP-Link Tapo Smart Bulb 4-Pack, including its energy-saving capabilities, color-changing options, and compatibility with smart home systems? How does it connect to Wi-Fi without the need for a hub, and what is the power consumption of the 8.7W B22 LED light bulb? Finally, what is the price of the Tapo L530B 4-Pack, and where can it be purchased?