Add Temporal Merge Policy for time-series data (#15620)

Introduces TemporalMergePolicy, a new merge policy designed for time-series workloads where documents
contain a timestamp field. The policy groups segments into time windows and merges segments within the same
window, but never merges segments across different time windows. This preserves temporal locality and
improves query performance for time-range queries.

---------

Co-authored-by: Shubham Sharma <shubham234727@gmail.com>
Co-authored-by: Michael Froh <msfroh@apache.org>

Author: 3 people

lucene/CHANGES.txt

@@ -155,28 +155,30 @@ New Features
   `Lucene104HnswScalarQuantizedVectorsFormat` replaces the now legacy `Lucene99HnswScalarQuantizedVectorsFormat`
    (Trevor McCulloch)
 
- * GITHUB#15271, GITHUB#15353: Extend `Lucene104ScalarQuantizedVectorsFormat` and `Lucene104HnswScalarQuantizedVectorsFormat` to
-   allow asymmetric quantization. The initially supported bits are single bit with 4 bit queries. This is a replacement
-   for the now legacy `Lucene102HnswBinaryQuantizedVectorsFormat` and `Lucene102BinaryQuantizedVectorsFormat`. To use
-   the new format for asymmetric binary quantization,
-   `Lucene104HnswScalarQuantizedVectorsFormat(ScalarEncoding.SINGLE_BIT_QUERY_NIBBLE, int, int)`
-    (Ben Trent)
-
- * GITHUB#15564: Further extend `Lucene104ScalarQuantizedVectorsFormat` and `Lucene104HnswScalarQuantizedVectorsFormat` to
-   allow asymmetric quantization with 2 bits and 4 bit queries. This can provide increased recall over single bit
-   with little additional storage cost and latency.
+* GITHUB#15271, GITHUB#15353: Extend `Lucene104ScalarQuantizedVectorsFormat` and `Lucene104HnswScalarQuantizedVectorsFormat` to
+  allow asymmetric quantization. The initially supported bits are single bit with 4 bit queries. This is a replacement
+  for the now legacy `Lucene102HnswBinaryQuantizedVectorsFormat` and `Lucene102BinaryQuantizedVectorsFormat`. To use
+  the new format for asymmetric binary quantization,
+  `Lucene104HnswScalarQuantizedVectorsFormat(ScalarEncoding.SINGLE_BIT_QUERY_NIBBLE, int, int)`
    (Ben Trent)
 
- * GITHUB#15415: Add fallback support to Lucene104ScalarQuantizedVectorsFormat getFloatVectorValues when there are
-   no full-precision vectors present (Pulkit Gupta)
+* GITHUB#15564: Further extend `Lucene104ScalarQuantizedVectorsFormat` and `Lucene104HnswScalarQuantizedVectorsFormat` to
+  allow asymmetric quantization with 2 bits and 4 bit queries. This can provide increased recall over single bit
+  with little additional storage cost and latency.
+  (Ben Trent)
+
+* GITHUB#15415: Add fallback support to Lucene104ScalarQuantizedVectorsFormat getFloatVectorValues when there are
+  no full-precision vectors present (Pulkit Gupta)
+
+* GITHUB#15468: Add support for `@SuppressAssertingFormats` annotation for fine-grained control over `AssertingCodec` formats (Prudhvi Godithi)
+
+* GITHUB#15518: Add support for post-collection faceting to the new faceting API in the sandbox module. (Egor Potemkin)
 
- * GITHUB#15468: Add support for `@SuppressAssertingFormats` annotation for fine-grained control over `AssertingCodec` formats (Prudhvi Godithi)
+* GITHUB#15620: Add Temporal Merge Policy for time-series data
 
- * GITHUB#15518: Add support for post-collection faceting to the new faceting API in the sandbox module. (Egor Potemkin)
+* GITHUB#14792: Introduced OffHeapQuantizedFloatVectorValues class to access float vectors when only quantized byte vectors are available in the index. (Pulkit Gupta)
 
- * GITHUB#14792: Introduced OffHeapQuantizedFloatVectorValues class to access float vectors when only quantized byte vectors are available in the index. (Pulkit Gupta)
- 
- * GITHUB#15591: Add SegmentOrder helper class to re-order segments at query time to align with sorts. (Alan Woodward)
+* GITHUB#15591: Add SegmentOrder helper class to re-order segments at query time to align with sorts. (Alan Woodward)
 
 Improvements
 ---------------------