Bevy Standard Widgets: Roadmap #19236

This is a tracking issue for the work described in discussion #16900 and referencing the prototype implementation which can be found here: https://github.com/viridia/bevy_core_widgets

• Upstream interaction state components (Checked, Hovering and friends)
• Core widgets, with examples
  • Button
  • Slider
  • Checkbox
  • Radio Group and Radio Button
  • Scrollbar
  • Number Scrubber** (edit numeric fields by dragging or keyboard)
  • Discrete Scrubber (edit discrete choices by dragging or keyboard)
  • Menu Button
  • Dialog
  • Text Input
  • Notification
  • Tooltips
  • Infotips
• Upstream cursor management framework
• Implement theming
• Implement opinionated editor widgets, with examples
  • Settle on final naming for opinionated widget collection
  • Button
  • Slider
  • Combo Slider (Slider with editable text)
  • Checkbox
  • Toggle Switch (using Core Checkbox)
  • Disclosure Triangle (prototype done)
  • Radio Group and Radio Button
  • Scrollbar and ScrollArea (prototype done)
  • List View (prototype done)
  • Combo Number Scrubber
  • Menu Button (prototype done)
  • Dialog
  • Text Input
  • Color Gradient Slider
  • Color Plane (2-axis picker)
  • Color Swatch with Alpha Grid
  • Swatch Grid
  • Swatch with dropdown color picker
  • Tab Deck
  • Tree View
  • Toasts
• Implement opinionated editor layout components (post-BSN)
  • Page layout variants
  • Toolbar
  • Sidebar

Spin-off tasks:

• Rounding options for sliders and other numeric inputs
• UI Transition animations framework: switch slider, disclosure triangle rotate, dialog enter/exit
• Feathers: Cursors for disabled widgets #20499
• Verify that variable-width fonts work in Bevy, and then replace FiraSans.
• Focus Rings
• AccessibleName component #20524
• Add Reflection support to CoreWidgets

** A "scrubber" is a numeric input widget which allows editing either by typing or dragging, as seen in blender.

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