What should have been a big week for Microsoft in the smart home has been dampened by Amazon launching the Echo Show – a large touchscreen-enabled hub. The focus should have been on Microsoft’s Cortana assistant, and its entrance into the marketplace, housed inside a Harman Kardon cylindrical speaker. Harman, now owned by Samsung, hasn’t announced a price for the Invoke speaker, but the device is set for a US launch in Q4. While Cortana first made its debut in the smart home via Insteon’s smartphone application, the move to a dedicated device is a strong step forward for the AI-based assistant – letting Microsoft catch up with rivals Amazon and Google. Notably, Cortana could use any Windows 10 device…