[B2] Sharing and social proof: member card, public hall of fame, referrals

Backlog. Everything that makes progression leave the app.

Ideas parked here

• Shareable member card. A generated image of the profile — level, 3 pinned badges, top works, seniority — in a cinema membership-card register. To be folded into the existing profile share button: instead of showing only a QR code, show a shareable profile card (with or without the QR embedded). This is the Rewind for a product with no history yet: it works after one month of use.
• Public hall of fame for the hosted instance (reviewers of the month, active profiles). Worth nothing until there is a user base — hosted only, well after launch.
• Rewarded referrals. Real growth lever, but needs an invitation flow, and it mixes growth with play — the front door for fake accounts polluting the leaderboard. Probably only after premium ships.

Dependencies

Profile share button (exists), [G4]/[G5] for what the card displays.