Aura fixes and enhancements

[jouni]

Blockers

• Consider adding -color to color properties, e.g. --aura-accent-light → --aura-accent-color-light [0.5 day]
• app-layout: move drawer-toggle[theme=permanent] from aura to the demo page [0.5 day] chore: remove app-layout selector that hides drawer-toggle in certain cases #10453
• consider if padding/gap values should be multiples of each other, to make it possible sum up two smaller ones to get a bigger one [1 day] - @rolfsmeds

Refactoring / Enhancement

• Refactor colors: [2 days] (refactor!: update aura accent and surface colors #10522)
  • fix Safari 17 support
  • improve computation overall (ensure contrast with different accent and bg color combinations/saturations), align colors across components (buttons, nav/menu items, palette text colors, etc)
  • surface color tweaking
    • improve how saturated accent colors affect the bg of nav items and buttons
• avatar: color-index should act as accent-color, and by default use “non-filled” styling. Then add a “filled” variant (like with button, side-nav, and tabs). (refactor: update avatar base styles and aura, add filled variant #10524)
• move custom prop definitions to a separate file that can be imported by IDEs for autocompletion purposes
  • do they supported/follow nested imports? Wouldn’t want to put all properties in a single file
• grid: filled-selection variant
• select value button: use font-weight-medium refactor: use font-weight medium for select value button #10489
• split-layout: minimal variant that turns the splitter accent color when hovered/active
• login overlay: entry & exit animations like in StarPass (and try to add a “shadow” under the overlay, like it’s floating in empty 3D space above a surface)

Bugs

• menu-bar-button: use expanded state in addition to active state to indicate when a menu is open
• verify: date-picker month calendar layout breaks with aura-base-size:17 (at least on retina screen)