[fix]ListPreSpan use GetTraceProcessor

[JqRrt]

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[CozeLoop]

Reviewed 1 backend file (excluding ignored paths). No issues identified; change is risk-free.

[CozeLoop]

变更无风险

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.

@@            Coverage Diff             @@
##             main     #340      +/-   ##
==========================================
+ Coverage   69.88%   70.10%   +0.22%     
==========================================
  Files         588      588              
  Lines       54452    54472      +20     
==========================================
+ Hits        38052    38190     +138     
+ Misses      13525    13396     -129     
- Partials     2875     2886      +11     

Flag	Coverage Δ
unittests	70.10% <100.00%> (+0.22%)	⬆️

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Files with missing lines	Coverage Δ
...bservability/domain/trace/service/trace_service.go	83.31% <100.00%> (ø)
backend/modules/observability/infra/repo/trace.go	84.00% <100.00%> (+1.92%)	⬆️

... and 6 files with indirect coverage changes

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