fix: byte-buddy-agent dep + S2184 + unused import

- pom.xml: add byte-buddy-agent as root test dep so
  dependency:properties resolves it in all modules (fixes CI
  ${net.bytebuddy:byte-buddy-agent:jar} unresolved error)
- PcoEncodingEncoder: change `- 1` to `- 1L` at all 3 weight
  writeBits calls so both subtraction operands are explicitly long (S2184)
- SparseEncodingDecoder: remove unused ByteOrder import

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: dfa1

pom.xml

@@ -73,6 +73,9 @@
 		<slf4j.version>2.0.18</slf4j.version>
 		<!-- coverage -->
 		<jacoco-maven-plugin.version>0.8.13</jacoco-maven-plugin.version>
+		<!-- byte-buddy-agent version must match what mockito-core pulls in transitively.
+		     Update this when bumping mockito.version (run: mvn dependency:tree -pl reader | grep byte-buddy-agent). -->
+		<bytebuddy.version>1.17.7</bytebuddy.version>
 		<!-- Generated sources (FlatBuffers + Protobuf) live under fbs/ and proto/. They
 		     are emitted by external code-gen and have no hand-written behaviour worth
 		     covering; counting them tanks the project-wide coverage ratio without
@@ -249,6 +252,18 @@
 		</dependencies>
 	</dependencyManagement>
 
+	<!-- byte-buddy-agent declared here so every module has it in its dependency tree,
+	     which allows maven-dependency-plugin:properties to resolve
+	     ${net.bytebuddy:byte-buddy-agent:jar} for the surefire -javaagent arg. -->
+	<dependencies>
+		<dependency>
+			<groupId>net.bytebuddy</groupId>
+			<artifactId>byte-buddy-agent</artifactId>
+			<version>${bytebuddy.version}</version>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
 	<build>
 		<pluginManagement>
 			<plugins>

reader/src/main/java/io/github/dfa1/vortex/reader/decode/SparseEncodingDecoder.java

@@ -30,7 +30,6 @@
 import java.lang.foreign.MemorySegment;
 import java.lang.foreign.ValueLayout;
 import java.nio.ByteBuffer;
-import java.nio.ByteOrder;
 
 /// Read-only decoder for {@code vortex.sparse}.
 public final class SparseEncodingDecoder implements EncodingDecoder {

writer/src/main/java/io/github/dfa1/vortex/writer/encode/PcoEncodingEncoder.java

@@ -305,7 +305,7 @@ private static MemorySegment buildClassicChunkMeta(
             int offsetBitsWidth = bitsToEncodeOffsetBits(dtypeSize);
             for (int i = 0; i < bins.size(); i++) {
                 PcoBinOptimizer.Bin bin = bins.get(i);
-                w.writeBits((long) weights[i] - 1, ansSizeLog);
+                w.writeBits((long) weights[i] - 1L, ansSizeLog);
                 w.writeBits(bin.lowerLatent(), dtypeSize);
                 w.writeBits(bin.offsetBits(), offsetBitsWidth);
             }
@@ -337,7 +337,7 @@ private static MemorySegment buildIntMultChunkMeta(
             w.writeBits(primaryBins.size(), 15);
             for (int i = 0; i < primaryBins.size(); i++) {
                 PcoBinOptimizer.Bin bin = primaryBins.get(i);
-                w.writeBits((long) primaryWeights[i] - 1, primaryAnsSizeLog);
+                w.writeBits((long) primaryWeights[i] - 1L, primaryAnsSizeLog);
                 w.writeBits(bin.lowerLatent(), dtypeSize);
                 w.writeBits(bin.offsetBits(), offsetBitsWidth);
             }
@@ -347,7 +347,7 @@ private static MemorySegment buildIntMultChunkMeta(
             w.writeBits(secondaryBins.size(), 15);
             for (int i = 0; i < secondaryBins.size(); i++) {
                 PcoBinOptimizer.Bin bin = secondaryBins.get(i);
-                w.writeBits((long) secondaryWeights[i] - 1, secondaryAnsSizeLog);
+                w.writeBits((long) secondaryWeights[i] - 1L, secondaryAnsSizeLog);
                 w.writeBits(bin.lowerLatent(), dtypeSize);
                 w.writeBits(bin.offsetBits(), offsetBitsWidth);
             }