[combobox] Fix inline filtering after selection in single mode

[atomiks]

• I have followed (at least) the PR section of the contributing guide.

Fixes #3976

[pkg-pr-new]

• base-ui-tanstack-start

• vite-css-base-ui-example

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/react@3978
  

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/utils@3978
  

commit: da72090

[mui-bot]

Bundle size report

Bundle	Parsed size	Gzip size
@base-ui/react	🔺+9B(0.00%)	🔺+4B(0.00%)

Details of bundle changes

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[greptile-apps]

Greptile Overview

Greptile Summary

Fixed a bug where inline filtering stopped working after selecting an item in single selection mode with a controlled open state. The root cause was that closeQuery was being set even in inline mode, which froze the filtering query. Since inline mode doesn't use a popup (and thus has no close animations), there's no need to preserve the query via closeQuery. The fix adds !inline guards in two locations where closeQuery is set for single mode, consistent with the existing logic for multiple mode.

Confidence Score: 5/5

• This PR is safe to merge with no risks
• The fix is targeted, logical, and follows existing patterns in the codebase (multiple mode already had similar inline checks). The test case comprehensively validates the fix, and the change is minimal with clear intent.
• No files require special attention

Important Files Changed

Filename	Overview
packages/react/src/combobox/root/AriaCombobox.tsx	Added !inline guards to prevent closeQuery from being set in inline mode, fixing filtering after selection
packages/react/src/combobox/root/ComboboxRoot.test.tsx	Added test case to verify filtering remains responsive after selection in inline mode with controlled open state

[mj12albert]

Works, tested with https://stackblitz.com/edit/c3dumgj3-1517b6td?file=package.json