fix(routes): close 404s, add legal pages, clean sitemap (THE-16)

[wschenk]

Summary

Closes broken marketing routes and adds the minimum legal surface needed for enterprise procurement and Buttondown TOS expectations. From the audit in THE-2, driven by THE-16.

What changed

Routes

URL	Behavior	Notes
/careers	→ /jobs	static redirect stub (Astro)
/products	→ account.thefocus.ai	external 302
/studio	→ /insights	was 404; nav dropdown label only
/contact	renders real page	mailto + newsletter signup; nav not yet rewritten
/privacy	renders real page	CEO-review stub: Buttondown + Plausible disclosure, deletion contact
/terms	renders real page	CEO-review stub
/sitemap.xml	emits <sitemapindex> → /sitemap-index.xml	for crawlers that default to /sitemap.xml

Sitemap cleanup

• @astrojs/sitemap now filters dev-only / scratch / redirect-stub pages out of /sitemap-0.xml: /drafts, /draft, /emails, /tags, plus all redirect stubs (/blog, /careers, /products, /studio, /ai-maturity, /learnings, /coding-agents, /recipes).
• Removed src/pages/draft.md — a stray scratch file that was getting served as /draft/.
• Fixed the broken #compare tag in the DeepResearch post — that's what was producing /%23compare/ in the sitemap.

Out of scope (intentional)

• /work → /case-studies (per the audit): there is uncommitted local work renaming /case-studies → /work, which inverts the redirect direction. I left that alone and worked from main. Once that rename lands, add a /case-studies → /work redirect in a follow-up.
• Global nav rewrite (issue boundary): /contact is reachable by URL but the nav's "Contact" item is still the existing mailto: link.
• Real HTTP 301s at the edge: Astro emits meta-refresh + canonical for static redirects. Upgrading to Cloudflare-level 301s is a deploy-config change, separate issue.

Test plan

• pnpm build passes (191 pages).
• dist/sitemap-0.xml no longer contains /drafts/, /draft/, /emails/, /tags/, /%23compare/, or any redirect stubs.
• dist/sitemap-0.xml contains /contact/, /privacy/, /terms/.
• dist/sitemap.xml returns a sitemapindex.
• dist/careers/index.html, dist/products/index.html, dist/studio/index.html are redirect stubs with noindex + canonical to the target.
• /privacy, /terms, /contact render with the standard BaseLayout and proper canonical URLs.
• CEO review of /privacy and /terms legal copy.
• Smoke each route on the live preview after deploy.

🤖 Generated with Claude Code (Paperclip CTO heartbeat for THE-16)