Warn when two @opentelemetry/api copies load

[unflxw]

Stacked on #1503.

Warn when two @opentelemetry/api copies load

An application loading two incompatible copies reports only some of its
spans, because the API hands a tracer that drops every span to whichever
copy loses the version comparison, which looks the same as an
application that produces none. The check reads the module cache rather
than walking node_modules, since a copy nothing loaded cannot cause
this, and says it once per process because which copies are loaded does
not change while one is running.

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[Copilot]

Pull request overview

Adds a runtime check to detect when multiple incompatible copies of @opentelemetry/api are loaded in the current process, and emits a warning so span loss due to OpenTelemetry API version arbitration is visible to the application operator.

Changes:

• Introduce loadedOpenTelemetryApiCopies + duplicateOpenTelemetryApiWarning to detect loaded @opentelemetry/api copies via require.cache and generate a human-readable warning.
• Call the new warning logic during Client startup when the OpenTelemetry SDK is initialized, logging to both console.warn and the internal logger.
• Add Jest coverage for the new helper module and a changeset entry documenting the new warning.

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated 3 comments.

File	Description
src/otel_api_copies.ts	New helpers to detect loaded @opentelemetry/api copies and produce an incompatibility warning message.
src/client.ts	Invoke the duplicate-API warning during OpenTelemetry initialization and log it.
src/__tests__/otel_api_copies.test.ts	Unit tests for the new helper module (copy detection + warning generation behavior).
.changesets/warn-about-duplicate-opentelemetry-api-copies.md	Changeset entry describing the new runtime warning behavior.

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 1 comment.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 2 comments.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated no new comments.

[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated no new comments.