#7712 fix(search): clear cached content after disconnect

Summary

• Clear cached Search results after a successful account disconnect or integration access change, and refresh server-rendered document pages.
• Reset document and chunk caches even when a file was opened directly, cancelling pending reads that could restore old content. Document keys have no organization scope, so these resets also cause other open knowledge-base details to refetch; Search results and source lists remain organization-scoped.

Type of Change

• Bug fix

Testing

51 focused tests passed, including success/failure after unmount, direct document and chunk caches without source lists, Search scope isolation, router refresh, and late response cancellation. App type-check, lint, all 46 repository audits, block registry, and docs manifest checks passed.

Checklist

• Code follows project style guidelines
• Self-reviewed my changes
• Tests added/updated and passing
• No new warnings introduced
• I confirm that I have read and agree to the terms outlined in the Contributor License Agreement (CLA)