discard2: Find even more URLs from server metadata

[TheTechRobo]

Let's split this up a bit

• Splashes
• Discovery splashes
• Widgets? (are they even available from the websockets?)
• Description (?)
• Banner
• Stickers

[upintheairsheep]

Custom emojis?

[TheTechRobo]

@upintheairsheep That's already done - see #15; if you mean for Discord History Tracker, that's impossible as DHT doesn't save that data.