feat(react-headless-components-preview): add color picker controls

[Dmytro Kirpa (dmytrokirpa)]

Motivation

Add an unstyled color-picker family to @fluentui/react-headless-components-preview. The controls reuse the state and interaction behavior extracted in #36517 while leaving layout and visual treatment to consumers.

Changes

• add headless ColorPicker, ColorArea, ColorSlider, and AlphaSlider components
• compose the controls from @fluentui/react-color-picker base hooks and shared context
• expose state through DOM data attributes for consumer styling
• support coordinated and standalone controlled or uncontrolled usage
• export the family through the color-picker package entry point
• add tests, Storybook examples, API output, bundle-size coverage, dependency metadata, lockfile update, and changefile

Review guidance

Review this PR relative to feat/color-picker-headless-base. The component layer intentionally adds no Griffel styles; story styles are consumer examples only.

Validation

• yarn nx run-many -t lint test -p react-headless-components-preview --nxBail

PR stack

1. test(react-color-picker): add hook state coverage #36527: add hook state coverage
2. feat(react-color-picker): expose headless base APIs #36517: expose reusable color-picker base APIs
3. This PR: add headless color-picker controls

Depends on #36517 and should be merged last.

[github-actions]

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