Share language and theme across the sites; prepare the 0.1.0 release (#13)

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

packages/landing/package.json

@@ -1,6 +1,6 @@
 {
   "name": "@prismshadow/penguin-landing",
-  "version": "0.0.1",
+  "version": "0.1.0",
   "private": true,
   "type": "module",
   "description": "PenguinHarness landing page (React + Vite + Tailwind CSS): multilingual, light/dark themes, benchmark showcase, and a local Markdown blog, deployed to GitHub Pages via GitHub Actions.",