feat: updated docs and added linting wf for repo content

[m-jahn]

No description provided.

[github-actions]

Super-linter summary

Language	Validation result
YAML_PRETTIER	Pass ✅

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[Copilot]

Pull request overview

Updates repository documentation and adds a PR-time YAML lint/format check to keep workflow/config YAML consistent in this reusable-workflows repo.

Changes:

• Expanded README.md with a “Workflows” section and usage examples for each reusable workflow.
• Added a new .github/workflows/yaml-formatting.yml workflow to run Super-Linter (YAML Prettier validation) on pull requests.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 2 comments.

File	Description
README.md	Documents available reusable workflows and provides example caller workflows.
.github/workflows/yaml-formatting.yml	Adds a PR-triggered YAML formatting/linting check via Super-Linter.

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[Copilot]

The note recommends pinning to @main as the "latest stable" version. main is a moving ref and not inherently stable; recommending it increases the risk of unexpected changes (and supply-chain exposure) for downstream repositories. Consider recommending a release tag (e.g. @v1 / @v1.2.3) or a commit SHA, and if @main is supported, document it as an opt-in for early adopters rather than "stable".

[Copilot]

Brand name casing: the link text should be "GitHub", not "Github".

Suggested change

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