Install Auth Across Applied AI Labs Apps

Don't re-derive the auth pattern — astro-knots already shipped it. This is the ai-labs handle: what to pull in, which DB, what to translate.

• Blueprint
• Authentication
• Turso
• libSQL
• Astro-DB
• Powabase
• Postgres
• GoTrue
• Svelte
• SvelteKit
• Applied-AI-Labs
• Cross-App-Pattern
• Signed-Link-Tokens
• OAuth
• Org-Model