Use OTel Status.Code to filter error traces in search_traces

[Sofiyan-Shaikh]

Which problem is this PR solving?

search_traces with with_errors=true was silently missing all OTel error traces because it filtered by the legacy Jaeger v1 error=true attribute tag instead of Status.Code = Error.
issues : #8553

Description of the changes

• Removed attributes.PutStr("error", "true") from buildQuery — the Jaeger v1 attribute tag is no longer sent to storage as a filter.
• Added post-retrieval filtering in the handle loop: traces where no span has Status.Code = Error are skipped when with_errors=true.

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How was this change tested?

• Updated TestSearchTracesHandler_Handle_WithErrorsFilter to assert error=true attribute is no longer injected into the query, and that the handler correctly filters non-error traces out.
• Added TestSearchTracesHandler_Handle_WithErrorsFilter_OTelStatusOnly covering the exact bug scenario — a GenAI trace with finish_reason=content_filter and Status.Code=Error but no error=true tag.
• Existing TestSearchTracesHandler_Handle_WithErrorsFilter_UsingMemoryStore continues to pass end-to-end.

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AI Usage in this PR (choose one)

See AI Usage Policy.

• None: No AI tools were used in creating this PR
• Light: AI provided minor assistance (formatting, simple suggestions)
• Moderate: AI helped with code generation or debugging specific parts
• Heavy: AI generated most or all of the code changes

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Checklist

• I have read https://github.com/jaegertracing/jaeger/blob/main/CONTRIBUTING_GUIDELINES.md
• I have signed all commits
• I have added unit tests for the new functionality
• I have run lint and test steps successfully: make lint test

[Copilot]

Pull request overview

Fixes search_traces’s with_errors=true behavior for OpenTelemetry traces by filtering based on OTel span Status.Code=Error instead of the legacy Jaeger v1 error=true attribute tag, ensuring OTel error traces are no longer silently omitted.

Changes:

• Remove injection of error=true into the storage query parameters.
• Add post-retrieval filtering to drop traces that have no spans with Status.Code=Error when with_errors=true.
• Update and add unit tests to validate the new filtering behavior, including the “OTel status only” bug scenario.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File	Description
cmd/jaeger/internal/extension/jaegermcp/internal/handlers/search_traces.go	Moves with_errors filtering from query-time (legacy tag) to post-retrieval filtering using OTel Status.Code.
cmd/jaeger/internal/extension/jaegermcp/internal/handlers/search_traces_test.go	Updates existing with_errors test expectations and adds coverage for OTel error traces without legacy error=true tags.

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[Sofiyan-Shaikh]

Hi @yurishkuro, I've implemented the fix for OTel error filtering and added logic to expand the search depth to ensure reliable results. I'd appreciate your review when you have a moment. Thanks!