Agreements bisecting fusions force a clone to recover

[gsvarovsky]

Noticed in the data-driven authorisation prototype.

Voiding of operations must only reverse journal entries with any process clock tick greater than that found in the agreement time. However, in m-ld, sequential journal entries may be fused (compressed). A fused entry may cross a process tick found in the agreement. In this case, it's not possible to arbitrarily "cut into" the fusion. In the prototype, the fusion is completely reversed; and if the clone is now missing data prior to the agreement, it goes into a 'recovery' mode (as if it has been offline).