[feat][backend]Support workflow automation tasks

[zero3233-bd]

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[codecov]

Codecov Report

❌ Patch coverage is 71.73913% with 13 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
...y/domain/task/service/taskexe/tracehub/backfill.go	50.00%	3 Missing and 2 partials ⚠️
backend/modules/observability/application/task.go	76.47%	2 Missing and 2 partials ⚠️
...s/observability/application/convertor/task/task.go	66.66%	1 Missing and 1 partial ⚠️
.../observability/domain/task/service/task_service.go	91.66%	0 Missing and 1 partial ⚠️
...servability/infra/mq/producer/backfill_producer.go	0.00%	1 Missing ⚠️

❌ Your patch status has failed because the patch coverage (71.73%) is below the target coverage (80.00%). You can increase the patch coverage or adjust the target coverage.

@@           Coverage Diff           @@
##             main     #267   +/-   ##
=======================================
  Coverage   68.49%   68.50%           
=======================================
  Files         585      585           
  Lines       54190    54218   +28     
=======================================
+ Hits        37120    37140   +20     
- Misses      14233    14238    +5     
- Partials     2837     2840    +3     

Flag	Coverage Δ
unittests	68.50% <71.73%> (+<0.01%)	⬆️

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

Files with missing lines	Coverage Δ
...modules/observability/domain/task/entity/filter.go	0.00% <ø> (ø)
...d/modules/observability/domain/task/entity/task.go	47.00% <ø> (ø)
.../observability/domain/task/service/task_service.go	79.10% <91.66%> (+0.97%)	⬆️
...servability/infra/mq/producer/backfill_producer.go	0.00% <0.00%> (ø)
...s/observability/application/convertor/task/task.go	74.30% <66.66%> (-0.19%)	⬇️
backend/modules/observability/application/task.go	72.14% <76.47%> (+0.78%)	⬆️
...y/domain/task/service/taskexe/tracehub/backfill.go	65.46% <50.00%> (-1.32%)	⬇️

... and 2 files with indirect coverage changes

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[CozeLoop]

Summary: Found a blocking type mismatch for TaskSource in DTO/DO convertors (compile-time error), plus an API design suggestion around ListTasks hard‑coded task_source filter. Please address the MUST FIX before merging.

MUST FIX:

• Convert TaskSource between *string and *task.TaskSource explicitly in application/convertor/task/task.go.

SUGGESTION:

• Only append default task_source filter when the client doesn’t specify it to keep API composability.