lint.yml, markdownlint.yml, and test.yml don't declare explicit permissions

[yakew7]

Problem

.github/workflows/dead-link-check.yml, pricing-review.yml, stale.yml, and welcome.yml all declare an explicit permissions: block scoped to what they need. lint.yml, markdownlint.yml, and test.yml don't declare one at all, so they silently inherit whatever the repo's default GITHUB_TOKEN permissions happen to be. That default is currently read-only at the repo level, but nothing in the workflow file itself guarantees that, and it's an easy setting to change by accident later.

What to do

Add permissions:\n contents: read to lint.yml, markdownlint.yml, and test.yml — the only access any of them needs (checkout + run a script).

Acceptance criteria

• All three workflows declare permissions: contents: read explicitly
• All three still pass on main

Scope: tiny, roughly 10 minutes. Good first issue.