[feat][trace] optimize ListTrajectoryOApi to single CK query

[cuichen01]

… switch

Reduce two ClickHouse reads in GetTrajectories to one by fetching all spans with full columns in a single query, then filtering in memory. Controlled by enable_single_query flag in trajectory_metadata_config, default off to preserve original behavior.

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Codecov Report

❌ Patch coverage is 75.51020% with 12 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...bservability/domain/trace/service/trace_service.go	73.33%	8 Missing and 4 partials ⚠️

@@            Coverage Diff             @@
##             main     #669      +/-   ##
==========================================
- Coverage   78.82%   78.82%   -0.01%     
==========================================
  Files         707      707              
  Lines       87823    87872      +49     
==========================================
+ Hits        69227    69264      +37     
- Misses      14607    14615       +8     
- Partials     3989     3993       +4     

Flag	Coverage Δ
unittests	78.82% <75.51%> (-0.01%)	⬇️

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Files with missing lines	Coverage Δ
...es/observability/domain/component/config/config.go	46.87% <100.00%> (+7.58%)	⬆️
...bservability/domain/trace/service/trace_service.go	89.56% <73.33%> (-0.36%)	⬇️

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