[YuvrajLamba01]

Description

Fixes #3928

Per the OpenTelemetry Prometheus/OpenMetrics compatibility specification, when multiple attribute keys sanitize to identical Prometheus label names, their values must be joined with ; ordered lexicographically by original attribute keys rather than overwriting earlier values.

• Group sanitized label keys in _collect_data_points\ and _create_info_metric.
• Order colliding pairs by original key and concatenate with ;.
• Add test coverage for sum, gauge, and target info collisions.

Type of change

• Bug fix (non-breaking change which fixes an issue)

Checklist:

• I am a human and not a bot
• I have run \ ox -e precommit\
• I have run \ ox -e typecheck\
• I have run the relevant tests and linting tox environments

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: YuvrajLamba01 / name: Yuvraj Lamba (5217b42)

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Waiting on reviewers · refreshed 2026-11-15 11:31 UTC

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[YuvrajLamba01]

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@YuvrajLamba01, this pull request was routed to reviewers. The handoff remains active across pushes until newer actionable human feedback arrives. Top-level feedback through this request will not return; unresolved review threads remain open.