[Accordion][Collapsible] Simplify shouldRender condition in AccordionPanel and CollapsiblePanel

[sai6855]

Simplify shouldRender condition in AccordionPanel and CollapsiblePanel

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[Copilot]

Pull request overview

This PR simplifies the render gating logic for AccordionPanel and CollapsiblePanel by removing a redundant !keepMounted check while keeping the same behavior for when panels should stay mounted or be rendered.

Changes:

• Simplified shouldRender in CollapsiblePanel to keepMounted || hiddenUntilFound || mounted.
• Simplified shouldRender in AccordionPanel to keepMounted || hiddenUntilFound || mounted.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated no comments.

File	Description
packages/react/src/collapsible/panel/CollapsiblePanel.tsx	Removes redundant boolean logic in the shouldRender condition without changing behavior.
packages/react/src/accordion/panel/AccordionPanel.tsx	Mirrors the same simplification for accordion panels to keep the logic consistent.

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[pkg-pr-new]

• base-ui-tanstack-start

• vite-css-base-ui-example

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/react@4338
  

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/utils@4338
  

commit: 9758383

[sai6855]

When shouldRender is evaluated, if keepMounted were true, the expression would already short-circuit. So !keepMounted is always true by the time the third operand is reached, making it redundant.

[mui-bot]

Bundle size report

Bundle	Parsed size	Gzip size
@base-ui/react	▼-8B(0.00%)	▼-10B(-0.01%)

Details of bundle changes

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