🔧 update lint configuration, clean up package.json, fix minor issues

[ctcpip]

• move to a simplified GH action for linting
• use updated markdownlint CLI and configuration
• set package to private to avoid accidental publication
• use linting tools directly instead of using npx
• remove package lock file, configure npmrc to not generate it
• fix markdown issues

note: the config right now ignores some md files due to the amount of manual clean up that would need to be done to those. that can be a follow-on later or we can ignore them forever.

Let's see some green check marks ✅ on new commits instead of red x's all the time. ❌😢