Summary: Added Humidistat Extractor Fan

Why It Matters: This shows a new product is being offered.

What Changed:

• A new product, "Humidistat Extractor Fan," was added under the "Solar Shading" section.
• A description for the new product was added: "On the topic of solar... also check out our Humidistat Extractor Fan - designed to automatically regulate humidity levels in your garden room."
• A new category link for "Humidistat Extractor Fan" was added with a link to its product page.