feat: Adds draft design doc for new block explorer REST API endpoints #7691

All 1 507 tests pass, 1 skipped in 28s

4 files - 22 425 suites +47 28s ⏱️ - 1h 1m 43s
1 508 tests +890 1 507 ✅ +920 1 💤 - 3 0 ❌ - 27
1 517 runs +387 1 516 ✅ +420 1 💤 - 3 0 ❌ - 30

Results for commit f1be973. ± Comparison against earlier commit 800e769.