fix(docs): filenames

[mfranzke]

Proposed changes

We still had some old references in our documentation to files that have been moved or renamed.

Types of changes

• Bugfix (non-breaking change that fixes an issue)
• New feature (non-breaking change which adds functionality)
• Refactoring (improvements to existing components or architectural decisions)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Further comments

[github-actions]

🔭🐙🐈 Test this branch here: https://db-ux-design-system.github.io/core-web/review/fix-docs-filenames

[Copilot]

Pull Request Overview

This PR fixes outdated file path references in documentation and configuration files that were pointing to old locations after files were moved or renamed. The changes ensure that import statements, documentation examples, and tooling configurations use the correct file paths.

Key changes:

• Updated CSS/SCSS import paths to reflect reorganized directory structure (e.g., color → colors, init → defaults)
• Added documentation validation script to package.json and updated its configuration
• Fixed file references in component development documentation

Reviewed Changes

Copilot reviewed 9 out of 9 changed files in this pull request and generated 1 comment.

Show a summary per file

File	Description
scripts/package.json	Added test script for documentation file reference validation
scripts/check-docs.js	Updated root directory path and excluded additional migration docs from validation
packages/foundations/docs/Colors.md	Fixed CSS/SCSS import paths from color to colors directory
packages/foundations/README.md	Updated theme import path from root to defaults subdirectory
packages/components/test/import-styles/simple-button/test.css	Updated multiple import paths to reflect new directory structure
packages/components/test/import-styles/simple-button/main.js	Updated import paths and improved comments for clarity
packages/components/README.md	Updated CSS import paths to use new directory structure
package.json	Removed duplicate test script that was moved to scripts workspace
docs/how-to-develop-a-component.md	Fixed SCSS import paths in component development guide