Document voices available on OEM Android devices

[HadrienGardeur]

There's an extremely large number of Android devices on the market and due to various tweaks applied by manufacturers, the list of available voices can vary greatly.

While it's nearly impossible to document them all, prioritizing the most popular OEM/devices could be a good strategy overall.

Samsung feels like the obvious OEM to focus on, considering their market share worldwide (they're the only ones competing with Apple for the crown).
Chinese OEMs such as Xiaomi, Oppo and Realme also have very decent market penetration outside of North America.

Since it's going to be difficult to get our hands on such a wide variety of devices, device farms could be a good option but we'll need to look into the list of devices that they actually have.

A demo page that returns the equivalent of window.speechSynthesis.getVoices() would be helpful for that task, since I doubt that we'll be able to easily open a console on these devices.