feat(profiling): Add benchmarks for OTLP/P converter

Author: jbachorik

dd-java-agent/agent-profiling/profiling-otel/build.gradle.kts

@@ -1,9 +1,42 @@
 plugins {
   `java-library`
+  id("me.champeau.jmh")
 }
 
 apply(from = "$rootDir/gradle/java.gradle")
 
+jmh {
+  jmhVersion = libs.versions.jmh.get()
+
+  // Fast benchmarks by default (essential hot-path only)
+  // Run with: ./gradlew jmh
+  // Override includes with: ./gradlew jmh -Pjmh.includes=".*"
+  includes = listOf(".*intern(String|Function|Stack)", ".*convertStackTrace")
+
+  // Override parameters with: -Pjmh.params="uniqueEntries=1000,hitRate=0.0"
+}
+
+// Full benchmark suite with all benchmarks and default parameters
+// Estimated time: ~40 minutes
+tasks.register<JavaExec>("jmhFull") {
+  group = "benchmark"
+  description = "Runs the full JMH benchmark suite (all benchmarks, all parameters)"
+  dependsOn(tasks.named("jmhCompileGeneratedClasses"))
+
+  classpath = sourceSets["jmh"].runtimeClasspath
+  mainClass.set("org.openjdk.jmh.Main")
+  args = listOf("-rf", "json")
+}
+
+repositories {
+  maven {
+    url = uri("https://s01.oss.sonatype.org/content/repositories/snapshots/")
+    mavenContent {
+      snapshotsOnly()
+    }
+  }
+}
+
 dependencies {
   implementation("io.btrace", "jafar-parser", "0.0.1-SNAPSHOT")
   implementation(project(":internal-api"))