Arrow array handle (opaque reference to native array).

An Array is the leaf node of the Arrow hierarchy — a single column of typed, contiguous values. Arrays are grouped into ExArrow.RecordBatch instances (one array per column), and batches are streamed via ExArrow.Stream.

Data lives in native (Rust) memory. This module provides a stable handle; copying to the BEAM heap is done only when explicitly requested through bridge modules such as ExArrow.Nx.column_to_tensor/2.

Position in the hierarchy

Schema ── Field (metadata: name, type, nullable)
            │
RecordBatch ── Array (one per column, shared row count)
                  │
Table ── RecordBatch (one or more batches, shared schema)
                  │
Stream ── RecordBatch (lazy sequence)

The Array handle itself is currently opaque on the Elixir side. Inspection functions (length, data type, null count) will be added as the NIF layer gains the corresponding entry points.