fix: Add status response model for POST/PUT/DELETE endpoints

[suchithh]

What

This change modifies the API. As per recommendations in thread #231 (comment), #231 was split into this PR which changes the API.

Changes

• Added a status response model to convert simple "ok" returns on success of POST, PUT, and DELETE endpoints into a proper Pydantic model

Related Issues

Partially fixes concern raised in #119 regarding having multiple return types. #231 (comment) is my reasoning behind why we should have standardization within each endpoint and across the API.

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 94.59%. Comparing base (b9cda65) to head (f4866c1).
Report is 68 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #239      +/-   ##
==========================================
- Coverage   95.06%   94.59%   -0.47%     
==========================================
  Files           5        5              
  Lines         324      370      +46     
==========================================
+ Hits          308      350      +42     
- Misses         16       20       +4     

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[alexgarel]

@suchithh I think we can't change the API without consulting the mobile app team (it's easy to change expected response in openfoodfacts-server, but it's harder on a mobile app, there is a risk of crash).

Can you open an issue in https://github.com/openfoodfacts/smooth-app/ to ask if it won't crash the mobile app if we change this ? (please detail you issue to help them answer quickly).

After that we can open an issue for openfoodfacts-server and openfoodfacts-explorer to leave them the time to change the code to handle the new API before merging this one.

[alexgarel]

@suchithh you might look for yourself in the mobile app code (or openfoodfacts-dart which is supporting it), because they might just check the returned http status, in which case it's ok to change the API.