chore: pin toolchain and add type checking

- Pin TypeScript as a direct dependency. It was only present transitively
  via typescript-eslint, so nothing enforced tsconfig.json and nine
  latent type errors had gone unnoticed.
- Add `pnpm typecheck` (`tsc --noEmit`) and document it.
- Add .npmrc with engine-strict, so the declared Node and pnpm ranges
  are actually enforced.
- Ignore doc_build/ in ESLint. It was unignored and reported 1650 errors
  from build output, which made lint unusable as a gate.
- Refresh README, CLAUDE.md, AGENTS.md and CONTRIBUTING.md to match the
  current structure, build targets and navigation rules.

package.json

@@ -1,13 +1,21 @@
 {
-  "name": "rspress-doc-template",
+  "name": "onixbyte-homepage",
   "version": "1.0.0",
   "private": true,
   "type": "module",
+  "packageManager": "pnpm@12.5.1",
+  "engines": {
+    "node": ">=24.0.0 <25.0.0",
+    "pnpm": ">=12"
+  },
   "scripts": {
     "build": "rspress build",
+    "build:com": "rspress build --config rspress.config.ts",
+    "build:cn": "rspress build --config rspress.cn.config.ts",
     "dev": "rspress dev",
     "format": "prettier --write .",
     "lint": "eslint .",
+    "typecheck": "tsc --noEmit",
     "preview": "rspress preview"
   },
   "dependencies": {
@@ -15,6 +23,7 @@
   },
   "devDependencies": {
     "@eslint/js": "^9.39.4",
+    "@rspress/plugin-sitemap": "2.0.11",
     "@tailwindcss/postcss": "^4.3.0",
     "@types/node": "^22.8.1",
     "@types/react": "^19.2.14",
@@ -25,6 +34,7 @@
     "react": "^19.2.6",
     "react-dom": "^19.2.6",
     "tailwindcss": "^4.3.0",
+    "typescript": "6.0.3",
     "typescript-eslint": "^8.58.1"
   }
 }