telemetry: lock the semconv version of the otel sdk

[jsternberg]

This change prevents changes to the otel version from affecting the otel
sdk version. This is done by copying the telemetry sdk implementation
locally and using our own choice for semconv from within that.

This prevents a schema conflict from happening since the otel version of
the sdk gets implicitly updated whenever the semconv changes while we
have to manually change ours. Now, we manually change both and they're
locked to each other.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 0% with 8 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
cli/command/telemetry.go	0.00%	8 Missing ⚠️

📢 Thoughts on this report? Let us know!

[Copilot]

Pull Request Overview

This PR locks the OpenTelemetry SDK semantic conventions version to prevent schema conflicts. The change updates OTel dependencies from v1.35.0 to v1.38.0 and implements a local telemetry SDK detector using a specific semconv version (v1.37.0) instead of relying on the SDK's default, which automatically updates with dependency changes.

Key Changes:

• Updated OTel core packages to v1.38.0 (otel, otel/metric, otel/trace)
• Replaced resource.WithTelemetrySDK() with a custom telemetrySDK detector
• Pinned semantic conventions to v1.37.0

Reviewed Changes

Copilot reviewed 3 out of 71 changed files in this pull request and generated no comments.

File	Description
vendor.mod	Updates OTel dependencies from v1.35.0 to v1.38.0 and transitive dependencies
vendor.sum	Reflects checksums for updated dependency versions
cli/command/telemetry.go	Implements custom telemetry SDK detector with locked semconv v1.37.0

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[thaJeztah]

Curious; was the OTEL version update needed for this to work, or would the previous version do as well?

[jsternberg]

Previous version would work.

[thaJeztah]

Updated this to continue using the current semconv and OTEL version; I moved those updates to #6578

[thaJeztah]

LGTM

CI is happy; I'll move the other PR out of draft later, but wanted this path in without the Otel bump, to keep the option open to include this in a 28.x patch release.