Adafruit TCA4307 Hot-Swap I2C Buffer with Stuck Bus Recovery

As we've been adding STEMMA QT connectors to our breakouts and dev boards, folks have been really enjoying the simplicity and speed of plugging in I2C sensors and devices for quick iteration and design. That's all good, but I2C wasn't really designed for hot-plugging. You're kinda supposed to have everything connected once on boot and never mess with it - I2C was specified for on-board connections. And, folks who have experimented with hot-plugging I2C devices eventually have discovered that if you plug in or unplug at the wrong moment you can cause the bus to hang due to an extra SCL pulse or an unexpected capacitive load.