feat(cc-range-selector): init component

[roberttran-cc]

What does this PR do?

• add a cc-range-selector component
• add a cc-range-selector-option sub component
• add a range-selector-dragging-controller to manage drag selection state
• add a trimArray utility function to src/lib/utils.js with comprehensive tests
• add CcRangeSelectEvent to common.events.js
• add CcRangeSelectorSelectCustom event for custom option selection
• add i18n translations (EN/FR) for error messages and UI labels
• integrate cc-range-selector in the form demo sandbox

How to review?

• check the commits
• check the stories in the preview
  • test both modes: 'single' for radio-like selection and 'range' for drag selection
  • test the drag interaction: mousedown → drag → mouseup (range mode)
  • test keyboard navigation
  • test the custom option feature with show-custom attribute
• play with the sandbox

What's to discuss

Feel free to challenge/comment on the following points:

• the component name (cc-range-selector)
• the property naming: mode, selection, showCustom
• the boundary-based selection approach ({ startValue, endValue }) vs storing full array
  • this optimizes memory but requires deriving the full array when needed
• the drag interaction pattern: clear → preview → apply (with rollback on outside click)
  • single-click without drag doesn't create a selection in range mode
• the handling of disabled options within a selected range:
  • they're visually included in the range
  • but excluded from form submission and the values array
  • disabled options at range boundaries are automatically trimmed on initialization
• the custom option button behavior:
  • clears current selection
  • dispatches custom event for parent handling
  • prevents multiple activations

[github-actions]

🔎 A preview has been automatically published : https://clever-components-preview.cellar-c2.services.clever-cloud.com/cc-range-selector/init/index.html.

This preview will be deleted once this PR is closed.