feat(read): decouple read batch lifetime from readers

[lxy-9602]

Purpose

Linked issue: close #259

Arrow and ORC buffers may be allocated from memory-pool adaptors owned by BatchReader. Because these buffers still access their allocator when they are released, Paimon previously required the BatchReader to outlive every ReadBatch returned by it.

This lifetime constraint couples readers with their returned batches and makes integration with downstream engines inconvenient and error-prone, as described in alibaba/paimon-cpp#126.

This PR removes that lifetime constraint for batches represented through the Arrow C Data Interface.
The memory-pool resources used by a batch, including Arrow and ORC pools, are retained by the root ArrowArray. They remain alive until the corresponding ArrowArray::release callback finishes. Therefore, a returned batch can safely outlive its BatchReader.

Consumers must treat the root ArrowArray as a complete ownership unit: keep, move, and release the entire structure through the Arrow C Data Interface. Moving individual child arrays out of the root ArrowArray is unsupported because those children do not independently retain the batch’s memory-pool lifetime.

Tests

API and Format

API impact:

• TableRead::CreateReader(const std::vector<std::shared_ptr<Split>>&) is now
  pure virtual, so concrete TableRead implementations must implement it.
• The BatchReader and ReaderBuilder lifetime contracts are explicitly documented.

Documentation

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