feat: add ckb-js-std package (nervosnetwork#38)

This PR introduces a TypeScript/JavaScript package designed to simplify the process of writing on-chain scripts. The package, named ckb-js-std, includes the following features:

- TypeScript definitions for bound functions, such as loadScript and loadWitness.
- High-level APIs written in TypeScript.
- Bundling tools for packaging scripts.
- A demo showcasing usage.
- Comprehensive documentation using TypeDoc.

.gitignore

@@ -54,3 +54,5 @@ dkms.conf
 .vscode
 
 build
+node_modules/
+dist/

package.json

@@ -0,0 +1,19 @@
+{
+  "private": true,
+  "workspaces": [
+    "packages/*"
+  ],
+  "scripts": {
+    "build:prepare": "pnpm -r install",
+    "build": "pnpm -r run build",
+    "docs": "typedoc"
+  },
+  "devDependencies": {
+    "esbuild": "0.24.2",
+    "eslint": "9.18.0",
+    "prettier": "3.4.2",
+    "typedoc": "0.27.6",
+    "typescript": "^5.7.3"
+  },
+  "pnpm": {}
+}