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]