[Agent Builder] Fix LLM assignment change not reflected without page refresh

[saikatsarkar056]

Summary

When an admin changes the LLM model assignment for Agent Builder in the Feature Settings page, the open Agent Builder session kept showing the old model until the user refreshed the entire page. This was confusing because the setting appeared saved but had no visible effect in the current session.

Screen Recording

Screen.Recording.2026-05-28.at.3.16.00.PM.mov

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Release note

Fixes Agent Builder not reflecting LLM model assignment changes made in Feature Settings without a full page refresh.

[kibanamachine]

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Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
agentBuilder	1.9MB	1.9MB	+177.0B
searchInferenceEndpoints	235.8KB	235.9KB	+39.0B
total			+216.0B

Page load bundle

Size of the bundles that are downloaded on every page load. Target size is below 100kb

id	before	after	diff
searchInferenceEndpoints	9.0KB	9.3KB	+278.0B

Unknown metric groups

ESLint disabled line counts

id	before	after	diff
searchInferenceEndpoints	2	1	-1

Total ESLint disabled count

id	before	after	diff
searchInferenceEndpoints	2	1	-1

History

cc @saikatsarkar056

[sphilipse]

This solution adds a permanent subscription on every page where the connector_selector is present, but the scenario it's checking for is exceedingly rare: having the conversation sidebar open, with a connector_selector, and editing the feature settings list.

I would rather solve this by forcing a page reload, or just ignore this edge case and let it be a little weird.

[saikatsarkar056]

Thanks, @sphilipse. Agreed that this is a very rare case. Let's ignore this. I will close the Pr.