[v2] Span Events native support and graphql error reporting

[rarguelloF]

What does this PR do?

v2 PR for #3176

Motivation

Reviewer's Checklist

• Changed code has unit tests for its functionality at or near 100% coverage.
• System-Tests covering this feature have been added and enabled with the va.b.c-dev version tag.
• There is a benchmark for any new code, or changes to existing code.
• If this interacts with the agent in a new way, a system test has been added.
• Add an appropriate team label so this PR gets put in the right place for the release notes.
• Non-trivial go.mod changes, e.g. adding new modules, are reviewed by @DataDog/dd-trace-go-guild.
• For internal contributors, a matching PR should be created to the v2-dev branch and reviewed by @DataDog/apm-go.

Unsure? Have a question? Request a review!

[datadog-datadog-prod-us1]

Datadog Report

Branch report: rarguelloF/AIDM-566/v2-span-events
Commit report: 834397c
Test service: dd-trace-go

✅ 0 Failed, 4440 Passed, 66 Skipped, 3m 50.09s Total Time

[pr-commenter]

Benchmarks

Benchmark execution time: 2025-03-31 15:17:02

Comparing candidate commit 27fd6cf in PR branch rarguelloF/AIDM-566/v2-span-events with baseline commit eb85ea1 in branch v2-dev.

Found 2 performance improvements and 1 performance regressions! Performance is the same for 52 metrics, 1 unstable metrics.

scenario:BenchmarkPartialFlushing/Disabled-24

• 🟥 allocated_mem [+7.889MB; +8.038MB] or [+2.366%; +2.411%]

scenario:BenchmarkPartialFlushing/Enabled-24

• 🟩 allocated_mem [-59.617MB; -54.867MB] or [-13.976%; -12.863%]
• 🟩 avgHeapInUse(Mb) [-19.053MB; -14.285MB] or [-27.621%; -20.708%]

[kakkoyun]

LGTM.

Same sentiment as in #3176 (review)