feat: add inexact not filter pushdown

[liujiwen-up]

Purpose

Linked issue: none.

This PR adds conservative SQL NOT pushdown after the exact residual reader semantics introduced around filter pushdown. SQL NOT cannot be treated as exact because Paimon's predicate evaluation uses two-valued predicate semantics while DataFusion must preserve SQL three-valued logic, especially for NULL values.

Brief change log

• Push translatable SQL NOT(expr) predicates to Paimon as Predicate::Not, while marking the DataFusion filter pushdown result as Inexact so the residual filter is preserved.
• Push case-sensitive NOT LIKE as an inexact negated LIKE predicate when the positive LIKE pattern can be translated; ILIKE remains unsupported.
• Track whether translated predicates require a residual filter, so partition-only NOT is not incorrectly classified as exact.
• Skip limit pushdown when the pushed filter requires a residual filter.
• Add conservative stats pruning for Predicate::Not(inner): prune only when the inner predicate must match every row in the file or data-evolution group; otherwise fail open.

Tests

• cargo fmt -- --check: passed
• git diff --check: passed
• PYO3_PYTHON=/opt/homebrew/bin/python3.12 cargo clippy --all-targets --workspace --features fulltext,vortex,mosaic -- -D warnings: passed
• cargo test -p paimon-datafusion filter_pushdown --lib: passed, 36 tests
• cargo test -p paimon-datafusion table::tests::test_scan_pushes_not_as_inexact_and_skips_limit_hint --lib: passed
• cargo test -p paimon-datafusion table::tests::test_scan_partially_translated_not_filter_prunes_partitions_but_skips_limit_hint --lib -- --exact: passed after make docker-up
• cargo test -p paimon-datafusion --test sql_context_tests test_not_filter_pushdown_keeps_sql_null_semantics: passed
• cargo test -p paimon predicate_stats --lib: passed, 19 tests
• cargo test -p paimon table_scan::tests::test_data_file_matches_not --lib: passed, 3 tests
• cargo test -p paimon table_scan::tests::test_data_evolution_group_matches_not --lib: passed
• cargo test -p paimon-datafusion --all-targets: passed through the previously failing test; local run then failed only on vector_search_top3 and vector_search_top6_returns_all because liblumina_py.dylib is not installed locally.

API and Format

No public API, manifest, snapshot, or storage format changes are introduced.

Documentation

No user-facing documentation changes are required. The behavior is covered by DataFusion pushdown and core stats unit tests.

[QuakeWang]

LGTM