refactor: align backend response status with UI

[frascuchon]

Description

After changes introduced in #4346, the pending status represents exactly what the missing status is. This PR deprecates the missing status for record responses in favor of a new pending status.

@damianpumar, maybe you can adat the changes in the frontend part.

Refs: #4346

Type of change

(Please delete options that are not relevant. Remember to title the PR according to the type of change)

• New feature (non-breaking change which adds functionality)
• Refactor (change restructuring the codebase without changing functionality)
• Improvement (change adding some improvement to an existing functionality)

Checklist

• I added relevant documentation
• I followed the style guidelines of this project
• I did a self-review of my code
• I made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• I filled out the contributor form (see text above)
• I have added relevant notes to the CHANGELOG.md file (See https://keepachangelog.com/)

[jfcalvo]

Is not possible to do a data migration updating old missing to pending so we can remove the old code?

[github-actions]

The URL of the deployed environment for this PR is https://argilla-quickstart-pr-4433-ki24f765kq-no.a.run.app

[damianpumar]

Hi Team!
Yes, for sure is necessary to align the frontend with backend. @frascuchon do you need to do the change now?
FYI: It would be no more than 15 minutes. Just let me know and add my commit here.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (6630d7b) 90.13% compared to head (b1e8987) 91.33%.
Report is 552 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #4433      +/-   ##
===========================================
+ Coverage    90.13%   91.33%   +1.19%     
===========================================
  Files          233      335     +102     
  Lines        12493    19326    +6833     
===========================================
+ Hits         11261    17651    +6390     
- Misses        1232     1675     +443     

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[damianpumar]

Hi guys! the CI is not working due to some failed tests, could you take a look?

[frascuchon]

Is not possible to do a data migration updating old missing to pending so we can remove the old code?

The missing status is not stored in the DB, since reflects the status when a record has no response. So, there is no need for a migration definition. Anyway, we must keep backward compatibility with 2 versions behind, letting client users adapt to the new change, so old code cannot be removed with these changes.