Design and implement a system for automatically rejecting requests from doomed clients

[beautifulentropy]

This bug is an umbrella/tracking bug, acting as a one-stop-shop to see progress on the multiple sub-tasks necessary to achieve this 2024 OKR.

• [x] #7407
• [x] #7499
  • [x] SFE: Handle count response from RA UnpauseAccount method
  • [x] SFE: Handle errors in first JWT parse differently from those in the submit parse
  • [x] SFE: Handle JWT expired different from other errors
• [x] #7536
• [x] #7619
• [x] #7475
• [x] #7618
• [x] #7617
• [x] Get feedback from the Forum on the new design
• [x] Write the deploy ticket for pausing our own test pairs
• [x] Write the deploy ticket for pausing the first 200 Subscriber pairs
• [x] Write the deploy ticket for pausing the remaining 7k+ Subscriber pairs
• [x] Write the deploy ticket for pausing the remaining 15k+ Subscriber pairs
• [x] Deploy to Production
• [ ] #7738

[pgporada]

• [x] https://github.com/letsencrypt/boulder/issues/7536