Add T64 and GORILLA packing transform codecs

[xiangfu0]

Stacked on #19305 (xiangfu0/codex/codec-stack/03-delta-codecs). Part of the split of #18229.

Summary

Adds the two packing transform codecs to the package-private codec runtime in
pinot-segment-local org.apache.pinot.segment.local.io.codec:

• T64CodecDefinition — frame-of-reference (FOR) bit-packing over fixed 64-value blocks for
  SV INT/LONG. Each block stores [baseline][bitWidth][bit-packed deltas] inside a
  [flag][count] frame. Partial last blocks still emit full 64-slot packed payloads (zero-filled
  tail) so payload size scales with block count.
• GorillaCodecDefinition — Gorilla-style XOR compression (Facebook VLDB 2015) for SV
  INT/LONG: verbatim first value, then per-value 0 bit for repeats or
  1 + window metadata + meaningful bits, with window reuse between consecutive XOR deltas.

Both are CodecKind.TRANSFORM stages with preservesTypedValueLayout() == false: they consume a
typed value array and emit a headered byte frame, so the existing CodecPipelineValidator
structural rule automatically enforces that they must be the last transform (only compression
stages may follow). No validator changes were needed — the rule generalizes from the synthetic
PACKING handler introduced in PR 02.

Both are registered in CodecRegistry.DEFAULT (names T64 / GORILLA are frozen on-disk
contract strings). Both codecs are corrupt-segment defensive: header flag/count validation runs
before any count-based short-circuit, bit widths and window (leading, width) pairs are
range-checked, and decodeInto enforces dst-capacity bounds.

Tests

• T64CodecDefinitionTest — round-trips for empty/single/all-equal/partial-block/max-range
  inputs; a parameterized sweep over every bitWidth 1..32 (INT) and 1..64 (LONG); an on-disk
  byte-layout pin test; encoded-size-within-maxEncodedSize bound checks; corrupt-segment
  defenses (bad flag, bad bitWidth, negative count, frame/column type mismatch).
• GorillaCodecDefinitionTest — round-trips for repeat/window-reuse/explicit-window transitions,
  boundary values, timestamp/counter-like sequences; corrupt-segment defenses including
  window-reuse-before-explicit.
• CodecPipelineValidatorTest — real-codec packing-rule scenarios through
  CodecRegistry.DEFAULT: DELTA,T64,LZ4 / DELTADELTA,GORILLA,ZSTD(3) / DELTA,T64 accepted;
  compression-after-packing (T64,ZSTD(3), GORILLA,SNAPPY, T64,LZ4,GZIP) accepted;
  T64,DELTA and T64,GORILLA rejected; type restrictions and no-arg enforcement;
  preservesTypedValueLayout() contract pinned to false for both.
• CodecRegistryTest — T64/GORILLA now resolve from the default registry (case-insensitive).
• TableConfigUtilsTest — a mis-ordered T64,DELTA,LZ4 codecSpec is still gate-rejected at
  config time with codecSpec is not supported yet for column: intCol.

Deliberately excluded (carried by later PRs)

• V7 raw forward index format (writer/reader that actually executes codec pipelines against
  segment chunks) — next PR in the stack (05, from local codec-split/07-v7-format).
• Opening the feature gate (config/creator/reader/reload surfaces accepting codecSpec,
  reload change-detection via canonical specs) — final PR (from local codec-split/08-reload-enable).
• Any public SPI exposure: both codecs are package-private inside io.codec; the only
  cross-package entry point remains CodecPipelineExecutor.

Why master stays safe with only this merged

The codecSpec feature gate is untouched and still closed: every config/creator/reader/reload
surface continues to throw codecSpec is not supported yet for column: %s, so no production
path can reach these codecs. The new classes are package-private additions to io.codec that are
only reachable through CodecPipelineExecutor, which nothing in production instantiates yet.
No on-disk format, wire protocol, or public API changes.

Verification

./mvnw -q -T 1C install -DskipTests -Ppinot-fastdev -pl pinot-segment-local -am
./mvnw -q test -Ppinot-fastdev -pl pinot-segment-local \
  -Dtest=T64CodecDefinitionTest,GorillaCodecDefinitionTest,CodecPipelineValidatorTest,CodecRegistryTest,DeltaCodecRoundTripTest,CodecPipelineExecutorTest \
  -Dsurefire.failIfNoSpecifiedTests=false
./mvnw -q test -Ppinot-fastdev -pl pinot-segment-local -Dtest=TableConfigUtilsTest \
  -Dsurefire.failIfNoSpecifiedTests=false
./mvnw spotless:apply license:format -pl pinot-segment-local
./mvnw checkstyle:check license:check -pl pinot-segment-local

Stack (split of #18229)

1. Fix forward index reader context lifecycle #19281 — Fix forward index reader context lifecycle (merged)
2. Fix delta forward index chunk caching #19282 — Fix delta forward index chunk caching (merged)
3. Add codec spec DSL and configuration plumbing #19284 — Codec spec DSL and configuration plumbing
4. Add bounded codec runtime and compression handlers #19285 — Bounded codec runtime and compression handlers
5. Add DELTA and DELTADELTA transform codecs #19305 — DELTA and DELTADELTA transform codecs
6. Add T64 and GORILLA packing transform codecs #19306 — T64 and GORILLA packing transform codecs ← this PR
7. Add V7 raw forward index format for codec pipelines #19307 — V7 raw forward index format
8. Support codecSpec on segment reload and enable codecSpec end to end #19308 — Reload/rewrite support, gate removal (enabling PR)
9. Add codec pipeline integration tests and design doc #19309 — Integration tests and design doc

Each PR is based on its predecessor's branch; GitHub retargets the next PR as each merges.