[switch][test] Add regression coverage and fix id doc

[atomiks]

Adds regression coverage for Switch cancellation and unchecked form values, plus aligns the id API docs with the current hidden-input/native-button behavior.

Changes

• Added tests that cancel onCheckedChange from root and hidden input clicks.
• Added Chromium coverage for custom value and uncheckedValue across an off/on/off cycle.
• Updated the Switch id JSDoc and generated API docs.

[pkg-pr-new]

• base-ui-tanstack-start

• vite-css-base-ui-example

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/react@4932
  

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/utils@4932
  

commit: fb60d61

[code-infra-dashboard]

Bundle size

Bundle	Parsed size	Gzip size
@base-ui/react	0B(0.00%)	0B(0.00%)

Details of bundle changes

Performance

Total duration: 1,225.74 ms +76.28 ms^(+6.6%) | Renders: 50 ⁽⁺⁰⁾ | Paint: 1,871.68 ms +129.88 ms^(+7.5%)

Test	Duration	Renders
Select mount (200 instances)	160.66 ms 🔺+29.26 ms(+22.3%)	3 (+0)
Popover mount (300 instances)	77.78 ms 🔺+15.56 ms(+25.0%)	1 (+0)
Select open (500 options)	54.44 ms 🔺+12.05 ms(+28.4%)	14 (+0)
Scroll Area mount (300 instances)	68.87 ms ▼-26.28 ms(-27.6%)	3 (+0)

8 tests within noise — details

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Check out the code infra dashboard for more information about this PR.

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