fix(takeLast): handle Infinity count

[yowainwright]

Description

takeLast(Infinity) currently allocates new Array(Infinity), which throws RangeError: Invalid array length.

This update assigns a growable buffer only for Infinity, while preserving the existing finite-count ring buffer and non-positive early-complete behavior.

• The regression test verifies that values are still emitted on completion.

Related issue (if exists)

• Refs fix(takeLast): prevent RangeError when count is Infinity #7608