seo: fix subdomain split, add canonical/sitemap/schema

[layerzerocontents]

Why

Searched "slaim.app" on Google. The landing isn't on page 1 at all — instead app.slaim.app (the PWA login wall) is #1. The rest of page 1 is spelling-variant junk (slime apps, "slim", Spotify artist named Slaim, slaim.io game, etc.). Two root causes:

1. Subdomain authority split — app.slaim.app is indexable and outranks the apex. Anyone clicking the top result lands on a login screen.
2. No entity disambiguation — Google has no signal to bind "slaim" the string to our software entity, so it fuzzy-matches to higher-authority lookalikes.

Raw HTML audit of slaim.app showed: no canonical, no JSON-LD, no sitemap, no robots.txt, and a <title> that's brand-only with zero category keywords.

What changed

Landing (/landing)

• <title>: Slaim — Just Slaim it. → Slaim — AI Slide Tutor for Med Students | PDF to Real Anki .apkg
  • OG/Twitter titles kept as the catchy brand version (social shares stay on-brand; SERP gets keywords)
• <link rel="canonical" href="https://slaim.app/">
• <meta name="robots" content="index, follow, max-image-preview:large">
• Two JSON-LD blocks: SoftwareApplication (with offers Free/$19/$39) + Organization, both with sameAs to Instagram + GitHub. This is the single biggest entity signal — tells Knowledge Graph "Slaim = this thing, not the artist / slime apps."
• /robots.txt referencing the sitemap
• /sitemap.xml covering /, /pricing, /marketplace, /privacy, /terms

App (/app)

• <meta name="robots" content="noindex, follow"> + canonical → https://slaim.app/ in index.html
• X-Robots-Tag: noindex, follow header in vercel.json — covers any PWA route past /, belt-and-suspenders with the meta tag
• follow is intentional: don't waste internal link equity that flows through to the apex

Expected impact

• 1-2 crawl cycles: app.slaim.app deindexed → slaim.app takes the Polar + Discord integration · remove yc-export #1 brand slot
• 2-4 weeks: sameAs + Schema starts disambiguating the entity in Knowledge Graph; fuzzy-match to "slime"/"slim" decreases
• Title keyword change ("AI Slide Tutor", "Med Students", "Anki .apkg") opens the door to ranking for category queries beyond brand

Follow-up (not in this PR)

• Google Search Console: verify both domains, submit sitemap, request indexing on top pages
• Bing Webmaster Tools (affects DuckDuckGo + ChatGPT search)
• Add more sameAs entries once TikTok / X / LinkedIn handles exist
• Product Hunt launch — single biggest external authority lever
• Directory listings: TheresAnAIForThat, Futurepedia, BetaList, Crunchbase
• Blog with category long-tail (/blog/pdf-to-anki, /blog/slaim-vs-anki)

Test plan

• After merge + Vercel deploy: curl -sI https://app.slaim.app | grep -i x-robots → returns noindex, follow
• curl -sL https://slaim.app | grep -E "canonical|application/ld\+json" → both present
• curl -sI https://slaim.app/sitemap.xml → 200
• curl -sI https://slaim.app/robots.txt → 200
• Validate JSON-LD: https://validator.schema.org/ with slaim.app URL → no errors
• Rich Results test: https://search.google.com/test/rich-results → SoftwareApplication detected
• OG share preview unchanged on Twitter/LinkedIn/Slack (we only changed <title>, not OG)