fix(API Usage): Update subscription cache from database-backed usage

[emyller]

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Changes

Contributes to https://github.com/Flagsmith/infrastructure/issues/334

Update subscription cache from database-backed analytics.

How did you test this code?

Unit tests.

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3 Skipped Deployments

Project	Deployment	Actions	Updated (UTC)
docs	Ignored		Mar 24, 2026 4:09pm
flagsmith-frontend-preview	Ignored	Preview	Mar 24, 2026 4:09pm
flagsmith-frontend-staging	Ignored	Preview	Mar 24, 2026 4:09pm

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 98.33%. Comparing base (94780fe) to head (708fe6a).
⚠️ Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #7024      +/-   ##
==========================================
+ Coverage   98.32%   98.33%   +0.01%     
==========================================
  Files        1335     1337       +2     
  Lines       49850    50010     +160     
==========================================
+ Hits        49013    49178     +165     
+ Misses        837      832       -5     

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[github-actions]

Docker builds report

Image	Build Status	Security report
ghcr.io/flagsmith/flagsmith-e2e:pr-7024	Finished ✅	Skipped
ghcr.io/flagsmith/flagsmith-frontend:pr-7024	Finished ✅	Results ✅
ghcr.io/flagsmith/flagsmith-api:pr-7024	Finished ✅	Results ✅
ghcr.io/flagsmith/flagsmith-api-test:pr-7024	Finished ✅	Skipped
ghcr.io/flagsmith/flagsmith:pr-7024	Finished ✅	Results ✅
ghcr.io/flagsmith/flagsmith-private-cloud:pr-7024	Finished ✅	Results ✅

[github-actions]

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

 10 passed

Details

 10 tests across 7 suites
 42.6 seconds
 970afd9
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Playwright Test Results (oss - depot-ubuntu-latest-arm-16)

 10 passed

Details

 10 tests across 7 suites
 49 seconds
 970afd9
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Playwright Test Results (private-cloud - depot-ubuntu-latest-16)

 2 passed

Details

 2 tests across 2 suites
 45.9 seconds
 970afd9
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Playwright Test Results (private-cloud - depot-ubuntu-latest-arm-16)

 1 passed

Details

 1 test across 1 suite
 59.9 seconds
 970afd9
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Playwright Test Results (oss - depot-ubuntu-latest-16)

 10 passed

Details

 10 tests across 7 suites
 46.3 seconds
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Playwright Test Results (oss - depot-ubuntu-latest-16)

 10 passed

Details

 10 tests across 7 suites
 42.6 seconds
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Playwright Test Results (oss - depot-ubuntu-latest-arm-16)

 10 passed

Details

 10 tests across 7 suites
 49.6 seconds
 7c98fc9
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Playwright Test Results (oss - depot-ubuntu-latest-arm-16)

 10 passed

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 10 tests across 7 suites
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 c4b4ec3
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Playwright Test Results (private-cloud - depot-ubuntu-latest-16)

 1 passed

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 1 test across 1 suite
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Playwright Test Results (private-cloud - depot-ubuntu-latest-arm-16)

 2 passed

Details

 2 tests across 2 suites
 1 minute, 1 second
 c4b4ec3
 🔄 Run: #15455 (attempt 1)

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

 10 passed

Details

 10 tests across 7 suites
 24.2 seconds
 48f96d9
 🔄 Run: #15460 (attempt 1)

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

 10 passed

Details

 10 tests across 7 suites
 53 seconds
 48f96d9
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Playwright Test Results (private-cloud - depot-ubuntu-latest-16)

 1 passed

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 1 test across 1 suite
 43.3 seconds
 48f96d9
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Playwright Test Results (private-cloud - depot-ubuntu-latest-arm-16)

 2 passed

Details

 2 tests across 2 suites
 1 minute, 15 seconds
 48f96d9
 🔄 Run: #15460 (attempt 1)

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

 10 passed

Details

 10 tests across 7 suites
 43.6 seconds
 708fe6a
 🔄 Run: #15464 (attempt 1)

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

 10 passed

Details

 10 tests across 7 suites
 45 seconds
 708fe6a
 🔄 Run: #15464 (attempt 1)

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

 3 passed

Details

 3 tests across 3 suites
 46.4 seconds
 708fe6a
 🔄 Run: #15464 (attempt 1)

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

 1 passed

Details

 1 test across 1 suite
 52.3 seconds
 708fe6a
 🔄 Run: #15464 (attempt 1)

[matthewelwell]

1 minor comment remaining.