feat: Add proxy for @line/liff-inspector

[odanado]

Description

Currently, the serve command’s --inspect option in liff-cli executes the @line/liff-inspector command with the --cert option.
liff-cli has a feature that can convert HTTP endpoints into HTTPS.
I used this feature to fix it so that @line/liff-inspector can be used without the --cert option.

As a result, it is now easier to combine @line/liff-inspector with tunneling tools like ngrok.

Usage

Run serve command with @line/liff-inspector

$ npx @line/liff-cli serve -l 1234567890-aBcDeFg -u http://localhost:5173/ --inspect
Debugger listening on ws://192.168.11.3:9222

You need to serve this server over SSL/TLS
For help, see: https://github.com/line/liff-inspector#important-liff-inspector-server-need-to-be-served-over-ssltls


Successfully updated endpoint url for LIFF ID: 1234567890-aBcDeFg.

→  LIFF URL:     https://liff.line.me/1234567890-aBcDeFg
→  Proxy server: https://localhost:9000/?li.origin=wss%3A%2F%2Flocalhost%3A9223%2F
connection from client, id: 1234567890-aBcDeFg
DevTools URL: devtools://devtools/bundled/inspector.html?wss=localhost:9223/?hi_id=1234567890-aBcDeFg

Run serve command with @line/liff-inspector and ngrok

$ npx @line/liff-cli serve -l 1234567890-aBcDeFg -u http://localhost:5173/ --inspect --proxy-type ngrok-v1

[odanado]

ref: https://www.npmjs.com/package/http-proxy#proxying-websockets