feat(experimentation): return feature object along with experiment entity

[Zaimwa9]

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Changes

• Attaches feature object (name and variants needed) along the experiment entity to avoid multiple requests or frontend re-association with paginated

How did you test this code?

• New tests

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Project	Deployment	Actions	Updated (UTC)
docs	Ready	Preview, Comment	May 27, 2026 2:42pm
flagsmith-frontend-preview	Ready	Preview, Comment	May 27, 2026 2:42pm
flagsmith-frontend-staging	Ready	Preview, Comment	May 27, 2026 2:42pm

[gemini-code-assist]

Code Review

This pull request introduces nested serialization for experiments by defining ExperimentFeatureSerializer and ExperimentListSerializer to include detailed feature and multivariate option data. It also updates the viewset to use this new serializer for list and retrieve actions. The reviewer identified two critical issues: first, the nested serialization will trigger an N+1 query problem unless select_related and prefetch_related are used to optimize the queryset; second, the custom transition actions (like start, pause, and complete) should also use the new serializer to prevent the frontend from receiving inconsistent data structures.

[github-actions]

Docker builds report

Image	Build Status	Security report
ghcr.io/flagsmith/flagsmith-e2e:pr-7609	Finished ✅	Skipped
ghcr.io/flagsmith/flagsmith-api-test:pr-7609	Finished ✅	Skipped
ghcr.io/flagsmith/flagsmith-frontend:pr-7609	Finished ✅	Results ✅
ghcr.io/flagsmith/flagsmith:pr-7609	Finished ✅	Results ✅
ghcr.io/flagsmith/flagsmith-private-cloud:pr-7609	Finished ✅	Results ✅
ghcr.io/flagsmith/flagsmith-api:pr-7609	Finished ✅	Results ✅

[github-actions]

Playwright Test Results (oss - depot-ubuntu-latest-16)

 1 passed

Details

 1 test across 1 suite
 33.3 seconds
 ed932fb
 🔄 Run: #17020 (attempt 1)

Playwright Test Results (oss - depot-ubuntu-latest-arm-16)

 1 passed

Details

 1 test across 1 suite
 42.8 seconds
 ed932fb
 🔄 Run: #17020 (attempt 1)

Playwright Test Results (private-cloud - depot-ubuntu-latest-16)

 2 passed

Details

 2 tests across 2 suites
 32.3 seconds
 ed932fb
 🔄 Run: #17020 (attempt 1)

Playwright Test Results (oss - depot-ubuntu-latest-16)

 1 passed

Details

 1 test across 1 suite
 38.9 seconds
 eaf6280
 🔄 Run: #17022 (attempt 1)

Playwright Test Results (private-cloud - depot-ubuntu-latest-arm-16)

 3 passed

Details

 3 tests across 3 suites
 36.6 seconds
 ed932fb
 🔄 Run: #17020 (attempt 1)

Playwright Test Results (oss - depot-ubuntu-latest-arm-16)

 1 passed

Details

 1 test across 1 suite
 36.7 seconds
 eaf6280
 🔄 Run: #17022 (attempt 1)

Playwright Test Results (private-cloud - depot-ubuntu-latest-16)

 3 passed

Details

 3 tests across 3 suites
 50.1 seconds
 eaf6280
 🔄 Run: #17022 (attempt 1)

Playwright Test Results (private-cloud - depot-ubuntu-latest-arm-16)

 2 passed

Details

 2 tests across 2 suites
 40.1 seconds
 eaf6280
 🔄 Run: #17022 (attempt 1)

Playwright Test Results (oss - depot-ubuntu-latest-arm-16)

 1 passed

Details

 1 test across 1 suite
 41.7 seconds
 86db405
 🔄 Run: #17023 (attempt 1)

Playwright Test Results (private-cloud - depot-ubuntu-latest-16)

 2 passed

Details

 2 tests across 2 suites
 32.1 seconds
 86db405
 🔄 Run: #17023 (attempt 1)

Playwright Test Results (private-cloud - depot-ubuntu-latest-arm-16)

 3 passed

Details

 3 tests across 3 suites
 1 minute, 5 seconds
 86db405
 🔄 Run: #17023 (attempt 1)

Playwright Test Results (oss - depot-ubuntu-latest-16)

 2 passed

Details

 2 tests across 2 suites
 37.9 seconds
 86db405
 🔄 Run: #17023 (attempt 1)

Playwright Test Results (oss - depot-ubuntu-latest-arm-16)

 1 passed

Details

 1 test across 1 suite
 41.8 seconds
 18cc27b
 🔄 Run: #17035 (attempt 1)

Playwright Test Results (oss - depot-ubuntu-latest-16)

 1 passed

Details

 1 test across 1 suite
 38.9 seconds
 18cc27b
 🔄 Run: #17035 (attempt 1)

Playwright Test Results (private-cloud - depot-ubuntu-latest-arm-16)

 1 passed

Details

 1 test across 1 suite
 41.8 seconds
 18cc27b
 🔄 Run: #17035 (attempt 1)

Playwright Test Results (private-cloud - depot-ubuntu-latest-16)

 1 passed

Details

 1 test across 1 suite
 37.3 seconds
 18cc27b
 🔄 Run: #17035 (attempt 1)

[github-actions]

Visual Regression

19 screenshots compared. See report for details.
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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.51%. Comparing base (d118da7) to head (18cc27b).
⚠️ Report is 1 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #7609   +/-   ##
=======================================
  Coverage   98.51%   98.51%           
=======================================
  Files        1439     1439           
  Lines       54690    54727   +37     
=======================================
+ Hits        53880    53917   +37     
  Misses        810      810           

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