feat: support batch incremental delta scans

[Pandas886]

Purpose

Linked issue: close #503

I'd like a small public API for batch incremental reads — basically "files between snapshot A (exclusive) and B (inclusive)" — without callers reinventing snapshot walking on top of TableScan.

This PR is intentionally thin: Delta + Auto selection only. Changelog / Diff come in follow-up PRs so review stays focused.

Brief change log

• Add IncrementalScanMode, IncrementalScan, IncrementalPlan, IncrementalSplit
• Range semantics: left-open / right-closed, empty range, out-of-bounds errors
• Delta: plan data files from APPEND snapshots in the range via existing scan helpers
• Auto: changelog-producer=none → Delta; otherwise resolves to Changelog (planning Changelog still fails loud until the next PR)
• Push partition/bucket filters through from ReadBuilder when planning
• TableRead::to_incremental_arrow for the data-split case

No new manifest reader code — it reuses what TableScan already does.

Tests

cargo test -p paimon --test incremental_batch_scan_test
cargo test -p paimon --lib
cargo fmt --all -- --check
cargo clippy -p paimon --all-targets --features fulltext,vortex -- -D warnings

API and Format

• New public scan types under paimon::table (also re-exported at crate root)
• No storage format change

Documentation

None yet — waiting until the SQL TVF lands so we document the whole story once. Can add a short rustdoc note if preferred.

Follow-ups

• feat: support existing changelog incremental reads #509 Changelog + AuditLogTable
• feat: support batch incremental diff reads #510 Diff mode
• feat: support DataFusion paimon_incremental_query #511 DataFusion paimon_incremental_query

[JingsongLi]

+1