fix: fix init not work on pnpm #1334 (#1347)

* fix: fix init not work on pnpm #1334

* doc: pnpm users must run init on project root

* Update bin.js

* Update bin.js

* Update get-started.md

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Co-authored-by: 键来！ <jmpecx@outlook.com>
Co-authored-by: typicode <typicode@gmail.com>

bin.js

@@ -5,7 +5,7 @@ import i from './index.js'
 let a = process.argv[2]
 
 if (a == 'init') {
-  let p = process.env.npm_package_json
+  let p = 'package.json'
   let d = JSON.parse(f.readFileSync(p))
   (d.scripts ||= {}).prepare = 'husky'
   w('package.json', JSON.stringify(d, null, /\t/.test() ? '\t' : 2) + '\n')