New observe by challenge and player views & follow by user in mks

[sei-jbritton]

Corresponding API changes: cmu-sei/Gameboard#33

• Overhaul of previous observer dashboard to support two new ways of observing: by challenge and by team/player
• Use of iframes to embed mks consoles into Gameboard UI instead of only viewing by new tab
• Both "Observe Challenges" and "Observe Teams" show a table where each row can expand to show a grid of consoles
• Consoles can be minimized, expanded, and opened in new tab
• The mapping of which users are on which consoles will update frequently
• Pinning rows to the top, searching, and sorting in the UI
• In mks, you can specify a user id in the url to follow users to the current vm they are looking at with /mks/?f=0&o=1&u=<USER_ID> instead of /mks/?f=0&o=1&s=<CHALLENGE_ID>&v=<VM_NAME>

This is a major update to the observer dashboard to have more intuitive groupings of VMs. A major considering was designing it to prevent reloading of the embedded iframes when data updates or change detection happens (e.g. a user switches consoles or a team score changes). This is the reason that some processing is done in the browser to have more control over what is reloaded.

[sei-mkaar]

Tested with Foundry Appliance 👍