Generate JSON by hand.

This improves performance further.

Before:

    Benchmark                                         Mode  Cnt       Score        Error  Units
    FormatterBenchmark.massivelyStructuredLogRecord  thrpt   10  137879.001 ±  30467.644  ops/s
    FormatterBenchmark.simpleLogRecord               thrpt   10  896085.217 ± 249890.421  ops/s
    FormatterBenchmark.structuredLogRecord           thrpt   10  553428.807 ± 194787.754  ops/s

After:

    Benchmark                                         Mode  Cnt        Score         Error  Units
    FormatterBenchmark.massivelyStructuredLogRecord  thrpt   10   220855.729 ±   56336.321  ops/s
    FormatterBenchmark.simpleLogRecord               thrpt   10  4456647.085 ± 1041546.047  ops/s
    FormatterBenchmark.structuredLogRecord           thrpt   10  1500896.509 ±  543358.587  ops/s

There is also a new benchmark:

    FormatterBenchmark.nestedLogRecord               thrpt   10   878620.441 ±  297024.983  ops/s

Change-Id: If3e323b133f8e3e3ff29431a92d1b1e500f9b8b2
diff --git a/core/pom.xml b/core/pom.xml
index 595cf38..5a97f43 100644
--- a/core/pom.xml
+++ b/core/pom.xml
@@ -33,10 +33,17 @@
       <optional>true</optional>
     </dependency>
     <dependency>
+      <groupId>jakarta.json</groupId>
+      <artifactId>jakarta.json-api</artifactId>
+      <version>2.1.3</version>
+    </dependency>
+    <dependency>
       <groupId>io.smallrye.common</groupId>
       <artifactId>smallrye-common-constraint</artifactId>
       <version>2.4.0</version>
     </dependency>
+
+    <!-- Include Parsson for backwards-compatibility. -->
     <dependency>
       <groupId>org.eclipse.parsson</groupId>
       <artifactId>parsson</artifactId>
@@ -57,16 +64,16 @@
     </dependency>
 
     <dependency>
-        <groupId>org.openjdk.jmh</groupId>
-        <artifactId>jmh-core</artifactId>
-        <version>1.35</version>
-        <scope>test</scope>
+      <groupId>org.openjdk.jmh</groupId>
+      <artifactId>jmh-core</artifactId>
+      <version>1.35</version>
+      <scope>test</scope>
     </dependency>
     <dependency>
-        <groupId>org.openjdk.jmh</groupId>
-        <artifactId>jmh-generator-annprocess</artifactId>
-        <version>1.35</version>
-        <scope>test</scope>
+      <groupId>org.openjdk.jmh</groupId>
+      <artifactId>jmh-generator-annprocess</artifactId>
+      <version>1.35</version>
+      <scope>test</scope>
     </dependency>
   </dependencies>