feat(objectstore): Add a (no-op) Objectstore endpoint

[lcian]

Adds a new endpoint that will proxy requests to Objectstore subject to org level permissions.
This does nothing for now, implementation will be added in a follow-up.
We will use our own JWT-based auth solution for authorizing operations, this should just proxy to the internal service.

This also adds our team to the CODEOWNERS for the relevant files, as that's required to add the endpoint.

[github-actions]

🚨 Warning: This pull request contains Frontend and Backend changes!

It's discouraged to make changes to Sentry's Frontend and Backend in a single pull request. The Frontend and Backend are not atomically deployed. If the changes are interdependent of each other, they must be separated into two pull requests and be made forward or backwards compatible, such that the Backend or Frontend can be safely deployed independently.

Have questions? Please ask in the #discuss-dev-infra channel.

[codecov]

Codecov Report

❌ Patch coverage is 79.31034% with 6 lines in your changes missing coverage. Please review.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
src/sentry/objectstore/endpoints/organization.py	76.92%	6 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           master   #103468      +/-   ##
===========================================
+ Coverage   80.34%    80.68%   +0.33%     
===========================================
  Files        9244      9245       +1     
  Lines      394946    394975      +29     
  Branches    25166     25166              
===========================================
+ Hits       317339    318699    +1360     
+ Misses      77179     75848    -1331     
  Partials      428       428              

[cursor]

Bug: DELETE method returns wrong HTTP status code

The delete method returns HTTP 200 instead of the standard HTTP 204 (No Content) for successful DELETE operations. REST conventions and the test framework expect DELETE endpoints to return 204 when successful, as seen in the get_success_response method which explicitly checks for 204 status codes on DELETE requests.