v0.2.0 feat: default frosting to social platforms

[superlowburn]

Summary

• default image and video frosting to supported social sites, including YouTube
• keep non-social sites clear unless the user explicitly frosts that exact site
• add simple on-page reveal, trust-site, and frost-site controls
• preserve subject frosting everywhere, including trusted sites
• keep video playback and autoplay untouched; frosting is visual only
• add multiple subjects, names, local suggestions, and clearer field guidance

Verification

• npm run typecheck
• npm run test:unit — 240 passed
• npm run test:e2e — 38 passed, 6 opt-in live checks skipped
• npm run build
• rebuilt and verified goggles-0.2.0.zip with manifest.json at its root

Live QA

• Reddit, CNN, The New York Times, and Fox News passed
• The Washington Post loaded successfully through Chrome after its headless HTTP/2 failure
• The Wall Street Journal stopped at human verification in Chrome; Camofox reached the homepage, but no extension pass is claimed because the Chrome extension was not loaded there

Closes #1

Follow-up onboarding work is tracked in #2.