Wave 1: add deps, crypto random utility, i18n helper, privacy fix, CI gates

- fix(deps): add zod and typescript to package.json
- feat(lib): add cryptographically secure random utility with TDD
- feat(lib): add client i18n helper with TDD
- fix(i18n): update privacy policy for crypto accuracy
- ci(deploy): add test and lint gates, fix SSH security

package.json

@@ -18,7 +18,8 @@
     "@astrojs/sitemap": "^3.2.1",
     "@tailwindcss/vite": "^4.0.0",
     "astro": "^4.16.0",
-    "tailwindcss": "^4.0.0"
+    "tailwindcss": "^4.0.0",
+    "zod": "^3.25.7"
   },
   "devDependencies": {
     "@eslint/js": "^10.0.1",
@@ -30,6 +31,7 @@
     "globals": "^17.6.0",
     "prettier": "^3.8.3",
     "prettier-plugin-astro": "^0.14.1",
+    "typescript": "^5.8.3",
     "typescript-eslint": "^8.59.2",
     "vitest": "^4.1.5"
   }