Expand exact handoff links and privacy-safe rich preview recipes

Goal

Provide reusable exact-link patterns that land an authenticated user on the right SaaS entity/action while producing a trustworthy, privacy-safe iMessage rich preview.

Scope

• Typed destinations and opaque short-lived token recipe.
• Auth redirect preservation and execution-time reauthorization.
• Signed-out, expired, revoked, deleted, tampered, forwarded, and cross-account handling.
• Generic, state-aware OG cards with cache/invalidation guidance.
• Standalone URL delivery and handoff analytics.

Acceptance criteria

• At least three destination recipes and a generic fallback card ship with tests.
• Preview crawlers cannot learn whether a private record exists.
• Sensitive identifiers, values, people, addresses, document content, or signed credentials never enter public metadata.
• A production canary and physical iPhone checklist verify actual unfurling behavior.