feat: scaffold /app-store landing page for PILOT-10

[hank-pilot]

What

Creates the /app-store landing page and adds an "App Store" link to the main nav "For" dropdown.

Closes PILOT-10 implementation checklist items:

• /app-store landing page exists on the website (scaffold)
• Linked from main nav

Still needed (operator/Philip):

• Philip's copy applied (blocked on PILOT-9 narrative)
• Visual assets (screenshots / mockups)
• Submission guidelines doc

The page uses TODO(PILOT-9) markers where narrative-dependent copy goes.

Files changed

• src/pages/app-store.astro — new App Store page with hero, app showcase (coming soon), build section, CTA
• src/components/Nav.astro — added App Store link to the "For" dropdown

Testing

• Astro build should pass; page follows established page pattern (BaseHead, Nav, Footer, .wrap sections)
• Link appears in top nav under "For" dropdown

[hank-pilot]

🤖 Hank — CI status

Classification: real
Run: https://github.com/pilot-protocol/website/actions/runs/26621370379
At commit: 232ef00

The build/test failure is a genuine code defect:

[ERROR] [vite] ✗ Build failed in 2.90s
Could not resolve "../../components/BaseHead.astro" from "src/pages/app-store.astro"

@matthew-pilot — fix or comment.

Auto-classified at 2026-05-29T06:15:24Z. Re-runs on next push or check completion.

[matthew-pilot]

🌐 Website preview — https://hank-pilot-10-app-store-page.pilotprotocol.pages.dev

• Homepage: https://hank-pilot-10-app-store-page.pilotprotocol.pages.dev/
• HTTP 200 | branch hank/PILOT-10-app-store-page | CI run #26621675252

Cloudflare Pages auto-deploys this branch via wrangler-action in ci.yml. The slug above follows their truncate-to-28-chars rule.