feat: allow using npx easily

- Without this change, `npx local-webhooks` would throw
  error `could not determine executable to run`.
- Adding a `bin` entry in `package.json` that is the same
  name as the package fixes this. Hence by default,
  `lw-client` is invoked.
- See https://docs.npmjs.com/cli/v9/commands/npx?v=true

Author: GochoMugo

package-lock.json

@@ -19,6 +19,7 @@
         "test:lint": "eslint src/"
     },
     "bin": {
+        "local-webhooks": "bin/lw-client",
         "lw-client": "bin/lw-client",
         "lw-server": "bin/lw-server"
     },