docs: replace stale Auth.js CLI references

[s0NRAYY]

☕️ Reasoning

The unscoped auth package now publishes the Better Auth CLI. Its secret command emits BETTER_AUTH_SECRET, while Auth.js reads AUTH_SECRET. The existing npx auth secret and npm exec auth secret guidance therefore runs another project's CLI and produces an environment key Auth.js does not consume.

This change:

• replaces the stale CLI commands in installation, deployment, environment, example, and TypeDoc guidance with openssl rand -base64 33
• tells installation readers to store the generated value as AUTH_SECRET
• redirects cli.authjs.dev to the current Auth.js installation guide instead of the former CLI repository

No runtime behavior or package dependencies change.

Validation:

• repository-wide search found no remaining npx auth secret, npm exec auth secret, Auth.js CLI, or github.com/nextauthjs/cli references
• pnpm format
• pnpm build:docs
• ESLint on the changed JavaScript and TypeScript files
• git diff --check

🧢 Checklist

• Documentation
• Tests — documentation-only change; no runtime behavior changed
• Ready to be merged

🎫 Affected issues

Related: nextauthjs/cli#29

📌 Resources

• Security guidelines
• Contributing guidelines
• Code of conduct
• Contributing to Open Source

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Project	Deployment	Actions	Updated (UTC)
auth-docs	Ready	Preview	Aug 31, 2026 11:03pm

1 Skipped Deployment

Project	Deployment	Actions	Updated (UTC)
next-auth-docs	Ignored	Preview	Aug 31, 2026 11:03pm

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