[PR] fix(cpp): preserve Gorilla sentinel values in aligned reads [tsfile]

["ColinLeeo (via GitHub)" <gi...@apache.org>]

ColinLeeo opened a new pull request, #883:
URL: https://github.com/apache/tsfile/pull/883

   ## Description
   
   Fixes data loss when reading aligned `DOUBLE` columns with parallel reading enabled.
   
   Gorilla encoding uses the canonical NaN bit pattern as its stream terminator. When the same bit pattern appears as a legitimate value, the regular batch decoder stops early. The parallel aligned-reader path previously treated the remaining predecoded buffer as valid, causing the NaN and subsequent values to be returned incorrectly.
   
   ## Changes
   
   - Use the aligned page bitmap as the authoritative non-null value count.
   - Continue decoding when a batch stops at an embedded Gorilla sentinel value.
   - Preserve legitimate NaN values and all values following them.
   - Apply the same count-aware behavior to fixed-width aligned read and skip paths.
   - Keep the normal batch decoding fast path unchanged.
   
   ## Tests
   
   Added a regression test covering an aligned `DOUBLE/GORILLA` page containing a NaN before the end of the page. It verifies that:
   
   - Reading returns `E_OK`.
   - The NaN value is preserved.
   - All subsequent values are returned correctly.
   - No rows are lost or replaced with zero values.
   
   Validation:
   
   - `TsFileReaderTest.*`: 18 tests passed
   - `*Gorilla*`: 25 tests passed


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Re: [PR] fix(cpp): preserve Gorilla sentinel values in batch reads [tsfile]

["ColinLeeo (via GitHub)" <gi...@apache.org>]

ColinLeeo merged PR #883:
URL: https://github.com/apache/tsfile/pull/883


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