rangefeed: add randomized tests for rangefeeds

Recently introduced data driven tests for rangefeeds: https://github.com/cockroachdb/cockroach/issues/82715 provid infrastructure to create range feeds and capture resulting data in order. It also provides validation checks that ensure rangefeed conforms to contract (event and checkpoint ordering and completeness guarantees).

While this fives us test coverage in static environment it would be beneficial to have tests that check that those guarantees hold when processors are restarted, ranges are split or merged while data is being written.

We can reuse infrastructure in place to add randomized tests.

Jira issue: CRDB-32269