telemetry: submit orchestrion_usage counter metric

[RomainMuller]

What does this PR do?

To make it easier to get data about orchestrion usage, start submitting a counter metric in telemetry for applications built with orchestrion.

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!

[pr-commenter]

Benchmarks

Benchmark execution time: 2024-12-09 13:59:49

Comparing candidate commit 78e6f39 in PR branch romain.marcadier/orchestrion-telemetry-metric with baseline commit 79a1f60 in branch main.

Found 0 performance improvements and 1 performance regressions! Performance is the same for 58 metrics, 0 unstable metrics.

scenario:BenchmarkHttpServeTrace-24

• 🟥 execution_time [+501.108ns; +559.092ns] or [+3.183%; +3.551%]