Switching some restate-core types to the new module style #7392

All 45 tests pass in 1m 53s

5 files - 2 5 suites - 2 1m 53s ⏱️ - 2m 32s
45 tests - 2 45 ✅ - 1 0 💤 - 1 0 ❌ ±0
114 runs - 68 114 ✅ - 65 0 💤 - 3 0 ❌ ±0

Results for commit 2ac41ac. ± Comparison against earlier commit 67bf47a.