[feat][backend] add search trace tree open api

[cuichen01]

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[codecov]

Codecov Report

❌ Patch coverage is 86.07306% with 61 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...bservability/domain/trace/service/trace_service.go	77.96%	10 Missing and 3 partials ⚠️
...dler/coze/loop/apis/observability_trace_service.go	0.00%	11 Missing ⚠️
backend/modules/observability/application/trace.go	89.53%	6 Missing and 3 partials ⚠️
...ace/service/trace/span_processor/clip_processor.go	89.88%	6 Missing and 3 partials ⚠️
...ckend/modules/observability/application/openapi.go	94.49%	4 Missing and 2 partials ⚠️
...kend/modules/observability/infra/repo/ck/common.go	61.53%	3 Missing and 2 partials ⚠️
.../observability/application/convertor/trace/span.go	0.00%	2 Missing and 1 partial ⚠️
...s/observability/infra/collector/event_collector.go	0.00%	3 Missing ⚠️
...er/coze/loop/apis/observability_open_apiservice.go	0.00%	2 Missing ⚠️

@@            Coverage Diff             @@
##             main     #217      +/-   ##
==========================================
+ Coverage   64.25%   64.34%   +0.08%     
==========================================
  Files         507      510       +3     
  Lines       56715    57115     +400     
==========================================
+ Hits        36445    36748     +303     
- Misses      17750    17823      +73     
- Partials     2520     2544      +24     

Flag	Coverage Δ
unittests	64.34% <86.07%> (+0.08%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files with missing lines	Coverage Δ
...ervability/domain/trace/entity/loop_span/filter.go	70.21% <100.00%> (ø)
...bservability/domain/trace/entity/loop_span/span.go	76.67% <100.00%> (+1.34%)	⬆️
...rvability/domain/trace/entity/otel/otel_pb2json.go	95.15% <100.00%> (ø)
...ackend/modules/observability/infra/config/trace.go	94.78% <100.00%> (+0.28%)	⬆️
...ckend/modules/observability/infra/repo/ck/spans.go	50.32% <100.00%> (+6.55%)	⬆️
backend/modules/observability/infra/repo/trace.go	61.12% <100.00%> (+0.46%)	⬆️
...er/coze/loop/apis/observability_open_apiservice.go	0.00% <0.00%> (ø)
.../observability/application/convertor/trace/span.go	52.90% <0.00%> (+13.85%)	⬆️
...s/observability/infra/collector/event_collector.go	0.00% <0.00%> (ø)
...kend/modules/observability/infra/repo/ck/common.go	61.53% <61.53%> (ø)
... and 5 more

... and 2 files with indirect coverage changes

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[taoyifan89]

default的配置和cozeloop都是一致的了是吧

[cuichen01]

预期default是目前所有配置的最小公共部分，上线前我再ckeck下