[field] Prevent rerenders when control is uncontrolled

[atomiks]

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

The useControlled/setValue wrapper was an unnecessary layer here

Fixes #3819

[pkg-pr-new]

• vite-css-base-ui-example

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/react@3820
  

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/utils@3820
  

commit: 33b4a22

[mui-bot]

Bundle size report

Bundle	Parsed size	Gzip size
@base-ui/react	▼-30B(-0.01%)	▼-14B(-0.01%)

Details of bundle changes

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[greptile-apps]

Greptile Summary

This PR optimizes performance for uncontrolled Field.Control inputs by removing unnecessary internal state updates on every keystroke. Previously, the component used useControlled hook's setter to track value changes even for uncontrolled inputs, causing the component to rerender on each keystroke.

The fix recognizes that for uncontrolled inputs, React doesn't need to track the value in state - the DOM element manages it via defaultValue. Now, only setDirty and setFilled state updates occur, which stabilize after the first keystroke (React's state setter bailout optimization prevents rerenders when setting the same value). This makes Base UI Input compatible with React Hook Form's performance expectations for uncontrolled inputs.

Key changes:

• Removed useStableCallback wrapper around value setter
• Eliminated unnecessary setValueUnwrapped calls for uncontrolled inputs
• Simplified value handling: controlled inputs get value prop, uncontrolled get defaultValue
• Added comprehensive test validating the rerender optimization

Confidence Score: 5/5

• This PR is safe to merge with minimal risk
• The change is a focused performance optimization that simplifies the code by removing unnecessary state tracking for uncontrolled inputs. The implementation correctly leverages React's standard uncontrolled input pattern using defaultValue, and includes a comprehensive test that validates the performance improvement. The change does not affect controlled input behavior and maintains backward compatibility.
• No files require special attention

Important Files Changed

Filename	Overview
packages/react/src/field/control/FieldControl.tsx	Removes unnecessary state tracking for uncontrolled inputs by eliminating the setValue wrapper and directly calling onValueChange, significantly reducing rerenders
packages/react/src/field/control/FieldControl.test.tsx	Adds test verifying uncontrolled inputs don't cause unnecessary rerenders after the first change, validating the performance optimization