[OPIK-5270] [E2E][T SDK] test: add exclude parameter tests for search traces

[andrescrz]

Details

Add test coverage for the exclude parameter on search_traces, as requested in PR #6098 review comments. This includes TypeScript SDK unit tests for the exclude option pass-through and E2E tests that verify the stream search endpoint correctly excludes feedback scores from the response while preserving all other trace fields.

Changes:

• TS SDK unit tests: Add exclude to existing option-override and integration tests, plus a standalone multi-field exclude test (3 modifications, 1 new test)
• E2E infrastructure: New /search-traces Flask endpoint wrapping client.search_traces() with exclude support, and corresponding searchTraces method on the TypeScript test helper client
• E2E test: New trace-search.spec.ts with control/treatment steps — verifies full trace payload (name, input, output, tags, metadata, feedback scores with values and source) then confirms exclude=["feedback_scores"] removes only scores

Change checklist

• User facing
• Documentation update

Issues

• OPIK-5270

AI-WATERMARK

AI-WATERMARK: yes

• Tools: Claude Code
• Model(s): Claude Opus 4.6
• Scope: full implementation
• Human verification: code review + iterative refinement of test assertions and conventions

Testing

• TS SDK unit tests: npx vitest run tests/unit/client/client-searchTraces.test.ts — 16/16 pass
• Pre-commit: pre-commit run --files <changed files> — clean
• E2E tests: Require running local stack (opik.sh + Flask test helper). Not run locally — to be validated by CI (@fullregression @tracing suite)

Documentation

N/A

[petrotiurin]

sdk looks good, thanks!