Migrate from OSSRH to Sonatype Central Portal

Update Maven publishing configuration to use Central Portal APIs ahead of OSSRH sunset on June 30, 2025:

- Replace nexus-staging-maven-plugin with central-publishing-maven-plugin
- Update distribution management URLs to use Central Portal endpoints
- Update CI settings.xml to use new Central Portal authentication

This migration ensures continued publishing capability after OSSRH EOL.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

Author: velo

.circleci/settings.xml

@@ -19,14 +19,14 @@
                           http://maven.apache.org/xsd/settings-1.0.0.xsd">
   <servers>
     <server>
-      <id>ossrh</id>
-      <username>${env.SONATYPE_USER}</username>
-      <password>${env.SONATYPE_PASSWORD}</password>
+      <id>central</id>
+      <username>${env.CENTRAL_TOKEN_USERNAME}</username>
+      <password>${env.CENTRAL_TOKEN_PASSWORD}</password>
     </server>
   </servers>
   <profiles>
     <profile>
-      <id>ossrh</id>
+      <id>central</id>
       <activation>
         <activeByDefault>true</activeByDefault>
       </activation>

pom.xml

@@ -77,12 +77,12 @@
 
   <distributionManagement>
     <repository>
-      <id>ossrh</id>
-      <url>https://oss.sonatype.org/service/local/staging/deploy/maven2/</url>
+      <id>central</id>
+      <url>https://central.sonatype.com/api/v1/publisher/deployments/upload/</url>
     </repository>
     <snapshotRepository>
-      <id>ossrh</id>
-      <url>https://oss.sonatype.org/content/repositories/snapshots</url>
+      <id>central</id>
+      <url>https://central.sonatype.com/api/v1/publisher/deployments/upload/</url>
     </snapshotRepository>
   </distributionManagement>
 
@@ -802,15 +802,14 @@
       <build>
         <plugins>
           <plugin>
-            <groupId>org.sonatype.plugins</groupId>
-            <artifactId>nexus-staging-maven-plugin</artifactId>
-            <version>1.7.0</version>
+            <groupId>org.sonatype.central</groupId>
+            <artifactId>central-publishing-maven-plugin</artifactId>
+            <version>0.8.0</version>
             <extensions>true</extensions>
             <configuration>
-              <serverId>ossrh</serverId>
-              <nexusUrl>https://oss.sonatype.org/</nexusUrl>
-              <autoReleaseAfterClose>true</autoReleaseAfterClose>
-              <stagingProgressTimeoutMinutes>15</stagingProgressTimeoutMinutes>
+              <publishingServerId>central</publishingServerId>
+              <autoPublish>true</autoPublish>
+              <waitUntil>published</waitUntil>
             </configuration>
           </plugin>
         </plugins>