ci: add link-check workflow (lychee)

[satyakwok]

Same pattern as the link-check workflow already shipped to awesome-sentrix, whitepaper, canonical-contracts, and dapp-starter. Lychee scans every markdown link on PR + push to main + weekly Monday 03:00 UTC cron. Non-blocking — mirrors the gitleaks workflow's policy.

Summary by CodeRabbit

• Chores
  • Enhanced documentation quality through automated link validation to ensure all references in markdown files remain accurate and functional.

[coderabbitai]

Caution

Review failed

The pull request is closed.

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro Plus

Run ID: fe7d0d9e-81d4-4037-91aa-c2b269f2bde8

📥 Commits

Reviewing files that changed from the base of the PR and between a2cc975 and 3cf9f5d.

📒 Files selected for processing (1)

• .github/workflows/link-check.yml

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📝 Walkthrough

Walkthrough

A new GitHub Actions workflow is added to automate link checking across markdown documentation. The link-check workflow runs on pull requests, pushes to main, a weekly Monday schedule, and manual trigger. It uses the Lychee action to validate links in all markdown files with configured concurrency, excluded patterns, and accepted HTTP status codes, with failures marked as non-blocking.

Changes

Automated Link Checking Workflow

Layer / File(s)	Summary
Workflow configuration and Lychee job setup .github/workflows/link-check.yml	Workflow triggers on PRs, main branch pushes, weekly cron, and manual dispatch with read-only contents permission. The lychee job checks all **/*.md files using the Lychee action with concurrency limits, URL exclusions, and specific HTTP accept codes, with fail: false for non-blocking execution.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

Poem

🐰 A workflow hops into the fold,
Link-checking markdown, bold and clear,
Every URL now verified with care,
On schedules weekly, PRs, and manual cheer—
Quality assured, no broken links here!

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch ci/link-check

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