EQL: Sequence improvements

[costin]

This is a meta ticket for must-have improvements now that EQL supports sequences.

• tie-breaker support
  Due to the distributed nature of ingestion it is quite possible for events to occur at the same time which does require a user-defined tie-breaker to establish serialization, separate from the document-based one in Elasticsearch (_doc).
  Further more this is used by the existing EQL test suite - without it some fails will surely fail.

• internal pagination
  In order to find X results, the sequence runtime must go through multiple internal pages before sending out the current results. Regardless of the client pagination, the algorithm needs to be able to handle its own pagination which is the norm for large datasets.

[elasticmachine]

Pinging @elastic/es-ql (:Query Languages/EQL)

[costin]

Completed by #58859 (internal pagination) and #57787 (tiebreaker support).