Automatically add any exposed http or tcp information to challenges

[detjensrobert]

Instead of having challenge authors add templates for {{ nc }} or {{ url }} to the description, we can automatically display that to the player like we do for file attachments.

This might need an extra config option for exposed pods config to configure whether to show them on the frontend or not (e.g. for OSINT challenges where the website is hosted in-cluster but the link needs to discovered`)