Add Dependabot configuration for automated dependency updates

[Copilot]

Description

Adds Dependabot configuration to automate dependency updates for npm packages and GitHub Actions.

Type of Change

• Bug fix (non-breaking change that fixes an issue)
• New formula/feature (non-breaking change that adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation update
• Performance improvement
• Code refactoring
• Test improvements

Related Issue

Addresses request to add Dependabot to the repository.

Changes Made

• Added .github/dependabot.yml with configuration for npm and GitHub Actions ecosystems
• Weekly update schedule on Mondays for both package types
• Grouped minor/patch updates by dependency type to reduce PR noise
• Conventional commit format (chore(deps):) for automated PRs

Formula Details (if applicable)

N/A

Testing

Test Coverage

• Added tests for new functionality
• Updated existing tests
• All tests pass locally (npm test)
• Build succeeds (npm run build)

Test Results

# Configuration validated with Python YAML parser
YAML syntax is valid!

Manual Testing

Verified dependabot.yml structure against GitHub's schema and tested with existing package.json and workflows.

Documentation

• Updated README.md (if needed)
• Added/updated JSDoc comments
• Updated CONTRIBUTING.md (if needed)
• Added usage examples (if applicable)

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published
• I have used the correct units (Kelvin for temperature, SI units for others)
• I have verified backward compatibility (or documented breaking changes)

Breaking Changes

• This PR introduces breaking changes
• I have updated the version number appropriately

Details of breaking changes:
N/A

Screenshots (if applicable)

N/A

Additional Notes

Configuration specifics:

• npm: 10 PR limit, groups dev/prod dependencies separately for minor/patch updates
• GitHub Actions: 5 PR limit
• Major version updates get individual PRs for careful review
• All PRs auto-labeled with dependencies and ecosystem type

Performance Impact

• No performance impact
• Performance improvement
• Potential performance regression (explain below)

Details:
N/A

Dependencies

• No new dependencies
• New dependencies added (list below with justification)

New dependencies:
N/A

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Reviewer Notes

• Key files to review: .github/dependabot.yml
• Areas needing special attention: Verify update schedule and PR limits align with team preferences
• Questions for reviewers: Adjust grouping strategy or update frequency if needed

Original prompt

Could we add dependabot to this repo?

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