feat: Add organization artifact metadata APIs

[maishivamhoo123]

Description

This PR implements the Organization Artifact Metadata APIs as requested in #3917.
This version corrects the scope from Repository to Organization level.

Changes

• Logic: Moved implementation to github/orgs_artifacts.go.
• Endpoints Added:
  • POST /orgs/{org}/artifacts/metadata/deployment-record
  • POST /orgs/{org}/artifacts/metadata/deployment-record/cluster/{cluster}
  • POST /orgs/{org}/artifacts/metadata/storage-record
  • GET /orgs/{org}/artifacts/{subject_digest}/metadata/deployment-records
  • GET /orgs/{org}/artifacts/{subject_digest}/metadata/storage-records
• Testing: Added comprehensive unit tests in github/orgs_artifacts_test.go.
• Generated: Updated github-accessors.go and github-stringify_test.go via script/generate.sh.

Checklist

• I have reviewed my own diff for unnecessary changes.
• All tests pass (script/test.sh).
• Code is linted (script/lint.sh).
• Ran script/generate.sh.

Fixes #3917

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 93.62%. Comparing base (5126e84) to head (48c79f6).

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #3944      +/-   ##
==========================================
+ Coverage   93.60%   93.62%   +0.01%     
==========================================
  Files         204      205       +1     
  Lines       17411    17461      +50     
==========================================
+ Hits        16298    16348      +50     
  Misses        912      912              
  Partials      201      201              

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[maishivamhoo123]

@gmlewis Sir can you please review the code?

[gmlewis]

Thank you, @maishivamhoo123, @alexandear , and @Not-Dhananjay-Mishra!
LGTM.
Awaiting second LGTM+Approval from any other contributor to this repo before merging.

cc: @stevehipwell - @zyfy29

[maishivamhoo123]

@Not-Dhananjay-Mishra can you please check once i think the latest pr is able to meet all your requirements?

[gmlewis]

Thank you, @maishivamhoo123!
All new tests need to add a call to testBadOptions to improve code coverage. Please search the repo for examples using testBadOptions and do likewise.

[gmlewis]

Thank you, @maishivamhoo123!
LGTM.
Awaiting second LGTM+Approval from any other contributor to this repo before merging.

cc: @stevehipwell - @alexandear - @zyfy29 - @Not-Dhananjay-Mishra

[maishivamhoo123]

@alexandear , @Not-Dhananjay-Mishra , @gmlewis can you please review the changes , I made all the suggested changes .

[Not-Dhananjay-Mishra]

LGTM