Add LockSupport TaskBlock profiling instrumentation

[kaahos]

What Does This Do

Add TaskBlock profiling instrumentation for LockSupport.park/unpark, including blocker and unblocking span attribution where available.

Motivation

LockSupport.park is widely used by executors, queues, schedulers, and virtual-thread internals. Capturing these park intervals as TaskBlock events makes parked time attributable to spans and easier to separate from active execution in wall-clock profiles.

Additional Notes

• Stacked on Add wallclock TaskBlock profiler support #11544
• Add DD_TRACE_LOCK_SUPPORT_ENABLED

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Jira ticket: [PROJ-IDENT]

[dd-octo-sts]

🔴 Java Benchmark SLOs — Performance SLO breach detected

Suite	Status
Startup	🔴 breach

SLO thresholds are defined here based on automatically generated metrics. A warning is raised when results are within 5% of the threshold.

PR vs. master results

Scenario	Candidate	master	Δ (95% CI of mean)
startup:insecure-bank:iast:Agent	13.99 s	13.94 s	[-0.3%; +1.0%] (no difference)
startup:insecure-bank:tracing:Agent	12.91 s	13.00 s	[-1.6%; +0.3%] (no difference)
startup:petclinic:appsec:Agent	16.88 s	16.73 s	[-0.1%; +1.9%] (no difference)
startup:petclinic:iast:Agent	16.88 s	16.90 s	[-0.9%; +0.7%] (no difference)
startup:petclinic:profiling:Agent	16.64 s	16.82 s	[-2.1%; -0.0%] (maybe better)
startup:petclinic:sca:Agent	16.76 s	16.13 s	[-0.4%; +8.3%] (no difference)
startup:petclinic:tracing:Agent	16.11 s	16.10 s	[-1.0%; +1.1%] (no difference)

Commit: 82ca3c9b · CI Pipeline · Benchmarking Platform UI

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Load and DaCapo benchmarks can be triggered manually in the GitLab pipeline. Results will appear in the Benchmarking Platform UI after completion.

[dd-octo-sts]

❌ New Groovy Files Detected

Please avoid introducing new .groovy files to this repository.

• dd-java-agent/instrumentation/datadog/profiling/lock-support/src/test/groovy/LockSupportProfilingDisabledForkedTest.groovy
• dd-java-agent/instrumentation/datadog/profiling/lock-support/src/test/groovy/LockSupportProfilingInstrumentationForkedTest.groovy

Instead, rewrite the new file(s) in Java / JUnit. See the How to Test With JUnit Guide for more details.

If this PR needs an exception, add the tag: override groovy enforcement label to bypass this workflow.