fix: vite-plugin-vue-devtools loaded unconditionally in all builds

[t0kubetsu]

Problem

vite.config.js includes vite-plugin-vue-devtools without checking the current mode:

plugins: [
  vue(),
  vueJsx(),
  vueDevTools(),   // ← always active
  tailwindcss(),
],

vite-plugin-vue-devtools injects a development inspector overlay into the page. Shipping it in a production build exposes internal component structure, store state, and routing information to end users.

Expected

Gate the plugin on the Vite mode:

import { defineConfig } from 'vite'

export default defineConfig(({ mode }) => ({
  plugins: [
    vue(),
    vueJsx(),
    mode === 'development' && vueDevTools(),
    tailwindcss(),
  ].filter(Boolean),
  // ...
}))

Impact

Production builds currently bundle and activate the Vue DevTools overlay, leaking application internals.