feat(utils): add values(start, end) slice accessor to DoubleEndedQueue

[luiz-lvj]

Summary

Ports OpenZeppelin/openzeppelin-contracts#6522 from openzeppelin-contracts 5.7.0.

Adds values(deque, start, end), returning the [start, end) slice of the queue as an array. Out-of-bound start/end are clamped to the queue length, mirroring the paginated values accessor in EnumerableSet.

[pepebndc]

LGTM

[pepebndc]

Add tests for values(start, end) in test/utils/structs/DoubleEndedQueue.test.js: empty queue, full range, end past the length, and start > end. The NatSpec can also state that start > end returns an empty array.

[luiz-lvj]

Done. The values(start, end) tests are in test/utils/structs/DoubleEndedQueue.test.js: empty queue (values returns empty array), full range (returns the full content for [0, length)), pagination across all begin/end combinations, end past the length (clamps end to length), and start > end (clamps start to end), plus a wraparound case. They landed in the PR itself, after this comment. On the NatSpec suggestion: upstream #6522 doesn't document the start > end behavior in the values docstring, so I left it matching upstream to keep the port exact.