v5.28.6 Group Plan workflow updates

API

• Chore: Locale files updated (@weblate)

Client

• Refactor: Group Plans landing pages unified to a single component with touched-up design (@SabreCat)
• Chore: Hide Amazon Payments buttons (@SabreCat)
• Fix: Show correct difficulty on hover for quest scrolls in a prior quest's drops info (@CuriousMagpie)
• Fix: Show site footer on static pages in test environments where "time travel" debug controls are enabled (@SabreCat)