op-node: extract unsafe-block processing from derivation code-path

[protolambda]

Description

Extracts the unsafe-block processing code-path from the EngineQueue and encapsulates it in a new clsync package. It buffers unsafe blocks, and applies as necessary, for step-wise CL sync.
The EL-sync is triggered as before still, upon new payloads received from gossip, not using the CL sync code-path.

This PR depends on #10580

Marked as do-not-merge until dependency is merged into develop.

This is the second step towards removal of the EngineQueue in favor of a more encapsulated pure derivation pipeline.

Tests

Adds missing unit tests: previously only the act of dropping an older unsafe block was tested.
Now it tests all combinations of existing unsafe head vs new unsafe payloads.

Metadata

Fix https://github.com/ethereum-optimism/protocol-quest/issues/270

[semgrep-app]

Semgrep found 2 golang_fmt_errorf_no_params findings:

• op-chain-ops/upgrades/l1.go
  • L704 - Triage
  • L707 - Triage

No fmt.Errorf invocations without fmt arguments allowed

_{Ignore this finding from golang_fmt_errorf_no_params.}

[semgrep-app]

Semgrep found 2 invalid-usage-of-modified-variable findings:

• op-conductor/conductor/service.go
  • L668-678 - Triage
  • L668-678 - Triage

Variable unsafeInNode is likely modified and later used on error. In some cases this could result in panics due to a nil dereference

_{Ignore this finding from invalid-usage-of-modified-variable.}

Semgrep found 1 todos_require_linear finding:

• packages/core-utils/src/common/bn.ts
  • L17 - Triage

Please create a GitHub ticket for this TODO.

_{Ignore this finding from todos_require_linear.}

[ajsutton]

LGTM. Really just Boy Scout, make the place a little better suggestions.

[protolambda]

Rebased on new finality-refactor base, which was rebased on develop

[protolambda]

Rebased on develop, dependency PR landed.