feat: Support updated $duration object format

[Copilot]

This PR implements support for the updated $dimension and $duration token formats introduced in design tokens specification PR #244.

Fixes #98

Changes

The specification changed dimension and duration tokens from string values to object values:

Old format:

{
  "$type": "dimension",
  "$value": "2rem"
}

New format:

{
  "$type": "dimension", 
  "$value": {
    "value": 2,
    "unit": "rem"
  }
}

Implementation

New Utility Functions

• Added src/utilities/dimensionUtils.ts with comprehensive utilities to handle both formats
• Functions for parsing, extracting values/units, and format detection
• Deprecation warning system for old string format usage

Updated Transformers

All dimension transformers now support both formats:

• dimension/pixelToRem
• dimension/remToPixel
• dimension/pixelUnitless

Backward Compatibility

• ✅ Existing tokens continue to work unchanged
• ✅ Old string format shows deprecation warnings encouraging migration
• ✅ New object format works without warnings
• ✅ All existing functionality preserved

Example Usage

// Old format (works but shows deprecation warning)
const oldToken = {
  name: 'spacing.large',
  $type: 'dimension',
  $value: '32px'
}

// New format (recommended)
const newToken = {
  name: 'spacing.medium', 
  $type: 'dimension',
  $value: {value: 24, unit: 'px'}
}

// Both work with existing transformers
dimensionPixelToRem.transform(oldToken)  // "2rem" + deprecation warning
dimensionPixelToRem.transform(newToken)  // "1.5rem" (no warning)

Test Coverage

• 16 new tests for utility functions
• Enhanced existing transformer tests to cover both formats
• Tests verify deprecation warnings work correctly
• Updated filter tests to validate both formats

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[lukasoppermann]

Changes this PR to focus only on the duration change.

[Copilot]

Changes this PR to focus only on the duration change.

Changed the PR to focus only on duration tokens as requested. Reverted all dimension-related changes and kept only the duration utilities and tests. Commit: 3efd083

[lukasoppermann]

The duration transformer has not been adjusted yet. Make sure to use the durationutils in the trasnformer and update the duration transformer test t include the new object values

[Copilot]

The duration transformer has not been adjusted yet. Make sure to use the durationutils in the trasnformer and update the duration transformer test t include the new object values

Added duration transformers that use the duration utilities and updated tests to include both new object format and old string format. Created duration/msToS and duration/sToMs transformers with comprehensive test coverage. Commit: e6ca92e

[lukasoppermann]

Merge the secondes to duration and ms to duration transfomers and tests into one and update the initial message in the PR.

[Copilot]

Merge the secondes to duration and ms to duration transfomers and tests into one and update the initial message in the PR.

Merged the duration transformers and tests into single files as requested. The two separate transformers (duration-ms-to-s and duration-s-to-ms) are now combined in src/transformer/duration.ts with their tests unified in src/transformer/duration.test.ts. Updated the PR description to reflect the consolidated approach. Commit: ae95057

[lukasoppermann]

Change this to have a durationToCss transformer that handles both s and ms depending on which on is used. Also update all tests.

[Copilot]

Change this to have a durationToCss transformer that handles both s and ms depending on which on is used. Also update all tests.

Created a unified durationToCss transformer that handles both s and ms units automatically. The transformer preserves the original unit choice while ensuring CSS compatibility. Updated all tests and replaced the separate duration/msToS and duration/sToMs transformers. Commit: 645136f