[drawer] Ignore swipes without an attributed direction when using snap points

[atomiks]

Fixes #5471

With snapPoints, the release logic decides to close from the vertical delta and release velocity alone. A mostly horizontal flick with a fast downward arc at lift passes those checks even though useSwipeDismiss never attributed a swipe direction to the gesture. The viewport then commits the closing choreography (data-ending-style, data-swipe-dismiss, snap point set to null), but the hook drops the release decision because it has no dismiss direction, so onOpenChange never fires and the popup stays visually dismissed while open remains true.

Changes

• When the gesture has no attributed direction, a would-close release settles on the nearest snap point instead of dismissing. Snap point navigation keeps working exactly as before for these gestures, since the sheet tracks their vertical component during the drag; only the close outcome is suppressed. The close is not deferred to the hook's fallback threshold loop because that loop checks both vertical directions when snap points are configured and would bypass the snap logic.
• Unattributed releases also reset nested swipe state, which the hook's deduped trailing progress update cannot do, so a nested parent no longer keeps data-nested-drawer-swiping and a stale swipe progress.
• Added regression tests for the unattributed fast flick, unattributed snap navigation, and nested cleanup.

[pkg-pr-new]

• base-ui-tanstack-start

• vite-css-base-ui-example

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/react@5477
  

  pnpm add https://pkg.pr.new/mui/base-ui/@base-ui/utils@5477
  

commit: 5b1a593

[code-infra-dashboard]

Bundle size

Bundle	Parsed size	Gzip size
@base-ui/react	🔺+91B(+0.02%)	🔺+21B(+0.01%)

Details of bundle changes

Performance

Total duration: 1,219.53 ms +12.95 ms^(+1.1%) | Renders: 76 ⁽⁺⁰⁾ | Paint: 1,922.31 ms +36.30 ms^(+1.9%)

Test	Duration	Renders
Menu open (500 items)	81.09 ms 🔺+19.01 ms(+30.6%)	11 (+0)
Select open (500 options)	53.16 ms 🔺+12.02 ms(+29.2%)	14 (+0)

13 tests within noise — details

Metric alarms

Test	Metric	Change
Menu open (500 items)	bench:paint	🔺 +31.49 ms
Menu open (500 items)	bench:paint#menu-open	🔺 +31.49 ms
Select open (500 options)	bench:paint	🔺 +31.51 ms
Select open (500 options)	bench:paint#select-open	🔺 +31.51 ms

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