What Does This Do

Adds PROFILING_CONTEXT_ATTRIBUTES_LLM_PHASE_ENABLED to ProfilingConfig and isLlmPhaseAttributeEnabled(ConfigProvider) to DatadogProfilerConfig.

Motivation

The llm.agent.phase context attribute slot must be registered at profiler startup — ContextSetter is built once and offsetOf() returns -1 for any name not present at construction time. This flag (default true) gates the registration, matching the PROFILING_CONTEXT_ATTRIBUTES_SPAN_NAME_ENABLED pattern and allowing operators to opt out without disabling the profiler.

Part of PROF-14858 (LLM phase attribution). Stacked: base (master) → [ddt-2-profiler] → [ddt-3-lc4j] → [ddt-4-demo].

Additional Notes

No behaviour change until the slot registration in the next PR in this stack.

Contributor Checklist

• Format the title according to the contribution guidelines
• Assign the type: and (comp: or inst:) labels in addition to any other useful labels
• Avoid using close, fix, or any linking keywords when referencing an issue
  Use solves instead, and assign the PR milestone to the issue
• Update the CODEOWNERS file on source file addition, migration, or deletion
• Update public documentation with any new configuration flags or behaviors
• Add your completed PR to the merge queue by commenting /merge. You can also:
  • Customize the commit message associated with the merge with /merge --commit-message "..."
  • Remove your PR from the merge queue with /merge -c
  • Skip all merge queue checks with /merge -f --reason "reason"; please use this judiciously, as some checks do not run at the PR-level
  • Get more information in this doc

Jira ticket: PROF-14861