[feat][backend] add offline metrics

[kidkidkid]

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[codecov]

Codecov Report

❌ Patch coverage is 38.18841% with 853 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...ules/observability/domain/metric/service/metric.go	54.01%	84 Missing and 19 partials ⚠️
...ervability/domain/metric/service/offline_metric.go	65.72%	78 Missing and 7 partials ⚠️
...ice/metric/model/model_total_error_count_metric.go	0.00%	33 Missing ⚠️
...e/metric/model/model_total_success_count_metric.go	0.00%	33 Missing ⚠️
...rvice/metric/tool/tool_total_error_count_metric.go	0.00%	33 Missing ⚠️
...ice/metric/tool/tool_total_success_count_metric.go	0.00%	33 Missing ⚠️
.../metric/service/service_span_error_count_metric.go	0.00%	27 Missing ⚠️
...etric/service/service_span_success_count_metric.go	0.00%	27 Missing ⚠️
...metric/service/service_trace_error_count_metric.go	0.00%	27 Missing ⚠️
...tric/service/service_trace_success_count_metric.go	0.00%	27 Missing ⚠️
... and 44 more

❌ Your patch check has failed because the patch coverage (38.18%) is below the target coverage (80.00%). You can increase the patch coverage or adjust the target coverage.

@@            Coverage Diff             @@
##             main     #326      +/-   ##
==========================================
- Coverage   69.88%   68.59%   -1.29%     
==========================================
  Files         588      608      +20     
  Lines       54452    55595    +1143     
==========================================
+ Hits        38052    38138      +86     
- Misses      13525    14560    +1035     
- Partials     2875     2897      +22     

Flag	Coverage Δ
unittests	68.59% <38.18%> (-1.29%)	⬇️

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

Files with missing lines	Coverage Δ
...dules/observability/domain/metric/entity/metric.go	100.00% <ø> (ø)
...etric/general/general_model_total_tokens_metric.go	100.00% <100.00%> (ø)
.../metric/general/general_tool_total_count_metric.go	100.00% <100.00%> (ø)
...rvice/metric/general/general_total_count_metric.go	100.00% <100.00%> (ø)
...tric/service/metric/model/model_duration_metric.go	100.00% <100.00%> (ø)
...ice/metric/model/model_input_token_count_metric.go	100.00% <100.00%> (ø)
...ce/metric/model/model_system_token_count_metric.go	100.00% <100.00%> (ø)
...c/service/metric/model/model_token_count_metric.go	100.00% <100.00%> (ø)
...tric/model/model_tool_choice_token_count_metric.go	100.00% <100.00%> (ø)
...n/metric/service/metric/model/model_ttft_metric.go	100.00% <100.00%> (ø)
... and 70 more

... and 3 files with indirect coverage changes

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[CozeLoop]

Code review comments posted: metrics suffix typo and usages, tenant error wrapping, DAO stub return, and one no-risk change.