[feat][backend] annotation related openapi

[kidkidkid]

What type of PR is this?

Check the PR title.

• This PR title match the format: [<type>][<scope>]: <description>. For example: [fix][backend] flaky fix
• The description of this PR title is user-oriented and clear enough for others to understand.
• Add documentation if the current PR requires user awareness at the usage level.
• This PR is written in English. PRs not in English will not be reviewed.

(Optional) Translate the PR title into Chinese.

(Optional) More detailed description for this PR(en: English/zh: Chinese).

en:
zh(optional):

(Optional) Which issue(s) this PR fixes:

[codecov]

Codecov Report

❌ Patch coverage is 82.89474% with 13 lines in your changes missing coverage. Please review.

Files with missing lines	Patch %	Lines
backend/modules/observability/application/trace.go	33.33%	1 Missing and 7 partials ⚠️
...er/coze/loop/apis/observability_open_apiservice.go	0.00%	4 Missing ⚠️
...bservability/domain/trace/service/trace_service.go	97.14%	0 Missing and 1 partial ⚠️

@@            Coverage Diff             @@
##             main     #155      +/-   ##
==========================================
+ Coverage   57.86%   59.58%   +1.71%     
==========================================
  Files         510      509       -1     
  Lines       52733    52297     -436     
==========================================
+ Hits        30516    31159     +643     
+ Misses      19847    18767    -1080     
- Partials     2370     2371       +1     

Flag	Coverage Δ
unittests	59.58% <82.89%> (+1.71%)	⬆️

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

Files with missing lines	Coverage Δ
...vability/application/convertor/trace/annotation.go	55.55% <100.00%> (+0.66%)	⬆️
...ckend/modules/observability/application/openapi.go	81.32% <100.00%> (+4.01%)	⬆️
...bility/domain/trace/entity/loop_span/annotation.go	71.05% <ø> (ø)
backend/modules/observability/infra/repo/trace.go	62.07% <100.00%> (+0.11%)	⬆️
...ckend/modules/observability/infra/rpc/auth/auth.go	54.34% <100.00%> (+54.34%)	⬆️
...bservability/domain/trace/service/trace_service.go	75.51% <97.14%> (+0.36%)	⬆️
...er/coze/loop/apis/observability_open_apiservice.go	0.00% <0.00%> (ø)
backend/modules/observability/application/trace.go	58.05% <33.33%> (ø)

... and 17 files with indirect coverage changes

---

Continue to review full report in Codecov by Sentry.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update 8ac6ef6...b190183. Read the comment docs.

🚀 New features to boost your workflow:

• ❄️ Test Analytics: Detect flaky tests, report on failures, and find test suite problems.
• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.