[P7-3] Social Sharing & Embed Meta Tags

[realproject7]

Context

§7.3 — share stories to Farcaster via sdk.actions.composeCast(). Story pages include fc:miniapp meta tags for rich embed previews (3:2 image, story title, current price, plot count, writer name).

Sub-tickets

• P7-3a: Add "Share to Farcaster" button on story pages — calls sdk.actions.composeCast() with a pre-filled message and story URL.
• P7-3b: Add fc:miniapp meta tags to story pages — title, description, image (3:2 ratio). Use Next.js metadata API. The image can be a dynamically generated OG image showing story title, writer, and plot count.

Proposal Reference

§7.3 (Social Features)

Dependencies

P3-4 (story page), P7-1 (miniapp SDK)

[realproject7]

T3 Note: Use /frontend-design skill in Claude Code when building UI components for this ticket. The design direction is terminal aesthetic — monospace, dark, outline-based, no fills, no shadows (§6.1).