rbac: optimize rbac assigned by roles query

[rissson]

Details

Same as #17015 but for roles.

---

Checklist

• Local tests pass (ak test authentik/)
• The code has been formatted (make lint-fix)

If an API change has been made

• The API schema has been updated (make gen-build)

If changes to the frontend have been made

• The code has been formatted (make web)

If applicable

• The documentation has been updated
• The documentation has been formatted (make docs)

[netlify]

✅ Deploy Preview for authentik-storybook ready!

Name	Link
🔨 Latest commit	089a3e8
🔍 Latest deploy log	https://app.netlify.com/projects/authentik-storybook/deploys/68dc06deb4039300084731ef
😎 Deploy Preview	https://deploy-preview-17052--authentik-storybook.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify project configuration.

[netlify]

✅ Deploy Preview for authentik-docs ready!

Name	Link
🔨 Latest commit	089a3e8
🔍 Latest deploy log	https://app.netlify.com/projects/authentik-docs/deploys/68dc06de47762b00085713eb
😎 Deploy Preview	https://deploy-preview-17052--authentik-docs.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify project configuration.

[netlify]

✅ Deploy Preview for authentik-integrations ready!

Name	Link
🔨 Latest commit	089a3e8
🔍 Latest deploy log	https://app.netlify.com/projects/authentik-integrations/deploys/68dc06de9dad500008da88ae
😎 Deploy Preview	https://deploy-preview-17052--authentik-integrations.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify project configuration.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 92.86%. Comparing base (54e1bcb) to head (089a3e8).
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #17052   +/-   ##
=======================================
  Coverage   92.86%   92.86%           
=======================================
  Files         845      845           
  Lines       46014    46026   +12     
=======================================
+ Hits        42729    42742   +13     
+ Misses       3285     3284    -1     

Flag	Coverage Δ
e2e	46.17% <18.75%> (-0.01%)	⬇️
integration	23.25% <0.00%> (-0.01%)	⬇️
unit	90.97% <100.00%> (+<0.01%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.