Bootstrap GSM tech debt

Taken from https://github.com/IntersectMBO/ouroboros-consensus/pull/808#issuecomment-1954913114, upon clicking the "Merge when ready" button.

- [x] s-r-p stanzas (see https://github.com/IntersectMBO/ouroboros-consensus/pull/808#discussion_r1490714381)
- [ ] Either move the GSM logic into the ChainDB and keep the GSM arguments as part of the ChainDB arguments (which would be encapsulated inside of openChainDB) or remove the argument from the ChainDB arguments and keep it as a NodeKernel-level thing.
- [ ] move the anti-thundering herd delay into the Diffusion Layer, _between_ the two states CaughtUp and OnlyBootstrap
- regression tests (code review and ad-hoc manual testing has already evidenced that they're _currently_ correct):
- [ ] `realMarkerFileView` regression tests
- [ ] `initializationLedgerJudgement` regression tests
- [ ] `realDurationUntilTooOld` regression tests
- [ ] The ChainSync client should signal idle exactly when and only when the `MsgAwaitReply` is processed.
- [ ] The ChainSync client subsequently should signal no-longer-idle exactly when and only when the next message is received.
- [x] #1149
- [ ] use `ArbitraryLedgerStateJudgement` from `ouroboros-network:sim-tests-lib`