[GH-2830] Fix S2 Geography WKB writer to emit OGC-conformant polygon closure

[zhangfengcdt]

Did you read the Contributor Guide?

• Yes, I have read the Contributor Rules and Contributor Development Guide

Is this PR related to a ticket?

• Yes, and the PR name follows the format [GH-XXX] my subject. Closes #<issue_number>

What changes were proposed in this PR?

Fix WKBGeography.getWKBBytes() to emit OGC-conformant (closed-ring) WKB.

How was this patch tested?

• PolygonRingClosureTest — single-ring POLYGON, asserts num_points = 5 and point[4] == point[0].
• MultiPolygonRingClosureTest — walks the MULTIPOLYGON byte stream and asserts each ring's closure.

Did this PR include necessary documentation updates?

• No, this PR does not affect any public API so no need to change the documentation.

[Copilot]

Pull request overview

This PR updates Sedona’s S2Geography WKB serialization to emit OGC-conformant polygon rings by explicitly writing the closing vertex (last point equals first) for POLYGON and MULTIPOLYGON rings, and adds byte-level tests to enforce this invariant.

Changes:

• Update WKBWriter.writePolygon to write numVertices + 1 coordinates per ring and duplicate the first vertex as the closing point.
• Update WKBWriter.writeMultiPolygon to apply the same N+1 ring closure behavior for each polygon/ring.
• Add unit tests that parse the emitted WKB byte stream to verify ring point counts and closure for POLYGON and MULTIPOLYGON.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
common/src/main/java/org/apache/sedona/common/S2Geography/WKBWriter.java	Writes OGC-closed rings by emitting an explicit closing coordinate for polygon rings.
common/src/test/java/org/apache/sedona/common/S2Geography/WKBWriterTest.java	Adds byte-level tests to assert ring closure for POLYGON and MULTIPOLYGON WKB output.

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[jiayuasu]

This code seems to be duplicate of Line 327?