chore: upgrade to vite 6 (#14363)

Upgrades the frontend toolchain to Vite 6 and tidies up the build config
along the way. Behavior is unchanged for end users; this is dev/build
infra.

## What changed
- `vite` 5.4 → 6.4, `@vitejs/plugin-vue` → 5.2, `vite-plugin-ruby` → 5.2
(with matching `vite_rails`/`vite_ruby` gem bumps).
- Dropped the `vite-node` 2.0.1 pnpm override — no longer needed now
that vitest 3 runs on Vite 6 directly.
- Split the single `vite.config.ts` into:
- `vite.config.ts` (app), `vite.lib.config.ts` (SDK), `vite.shared.ts`
(aliases / Vue options), `vitest.config.ts` (tests).
- `pnpm build:sdk` now selects the SDK config explicitly instead of
branching on `BUILD_MODE=library`. SDK output path is unchanged
(`public/packs/js/sdk.js`).

No changes needed to Docker images, deployment scripts, or CI — Node 24
and pnpm 10 are already past Vite 6's floor, and the rake
`assets:precompile` hook still drives the SDK build via `pnpm`.

## How to test
- `pnpm dev` and verify the dashboard, widget, and survey routes load
and HMR works.
- Load a Chatwoot site widget on a test page and confirm `sdk.js` is
served and the widget mounts.
- `RAILS_ENV=production bundle exec rake assets:precompile` and confirm
`public/packs/js/sdk.js` plus the rest of the manifest are produced.
- `pnpm test` for the JS suite.

---------

Co-authored-by: Sivin Varghese <64252451+iamsivin@users.noreply.github.com>
Co-authored-by: Sony Mathew <2040199+sony-mathew@users.noreply.github.com>

vite.config.ts

@@ -1,50 +1,11 @@
-/// <reference types="vitest" />
-
-/**
-What's going on with library mode?
-
-Glad you asked, here's a quick rundown:
-
-1. vite-plugin-ruby will automatically bring all the entrypoints like dashbord and widget as input to vite.
-2. vite needs to be in library mode to build the SDK as a single file. (UMD) format and set `inlineDynamicImports` to true.
-3. But when setting `inlineDynamicImports` to true, vite will not be able to handle mutliple entrypoints.
-
-This puts us in a deadlock, now there are two ways around this, either add another separate build pipeline to
-the app using vanilla rollup or rspack or something. The second option is to remove sdk building from the main pipeline
-and build it separately using Vite itself, toggled by an ENV variable.
-
-`BUILD_MODE=library bin/vite build` should build only the SDK and save it to `public/packs/js/sdk.js`
-`bin/vite build` will build the rest of the app as usual. But exclude the SDK.
-
-We need to edit the `asset:precompile` rake task to include the SDK in the precompile list.
-*/
 import { defineConfig } from 'vite';
 import ruby from 'vite-plugin-ruby';
-import path from 'path';
 import vue from '@vitejs/plugin-vue';
+import { aliases, vueOptions } from './vite.shared';
 import yaml from '@rollup/plugin-yaml';
 
-const isLibraryMode = process.env.BUILD_MODE === 'library';
-const isTestMode = process.env.TEST === 'true';
-
-const vueOptions = {
-  template: {
-    compilerOptions: {
-      isCustomElement: tag => ['ninja-keys'].includes(tag),
-    },
-  },
-};
-
-let plugins = [ruby(), vue(vueOptions), yaml()];
-
-if (isLibraryMode) {
-  plugins = [];
-} else if (isTestMode) {
-  plugins = [vue(vueOptions), yaml()];
-}
-
 export default defineConfig({
-  plugins: plugins,
+  plugins: [ruby(), vue(vueOptions), yaml()],
   css: {
     preprocessorOptions: {
       scss: {
@@ -52,74 +13,5 @@ export default defineConfig({
       },
     },
   },
-  build: {
-    rollupOptions: {
-      output: {
-        // [NOTE] when not in library mode, no new keys will be addedd or overwritten
-        // setting dir: isLibraryMode ? 'public/packs' : undefined will not work
-        ...(isLibraryMode
-          ? {
-              dir: 'public/packs',
-              entryFileNames: chunkInfo => {
-                if (chunkInfo.name === 'sdk') {
-                  return 'js/sdk.js';
-                }
-                return '[name].js';
-              },
-            }
-          : {}),
-        inlineDynamicImports: isLibraryMode, // Disable code-splitting for SDK
-      },
-    },
-    lib: isLibraryMode
-      ? {
-          entry: path.resolve(__dirname, './app/javascript/entrypoints/sdk.js'),
-          formats: ['iife'], // IIFE format for single file
-          name: 'sdk',
-        }
-      : undefined,
-  },
-  resolve: {
-    alias: {
-      vue: 'vue/dist/vue.esm-bundler.js',
-      components: path.resolve('./app/javascript/dashboard/components'),
-      next: path.resolve('./app/javascript/dashboard/components-next'),
-      v3: path.resolve('./app/javascript/v3'),
-      dashboard: path.resolve('./app/javascript/dashboard'),
-      helpers: path.resolve('./app/javascript/shared/helpers'),
-      shared: path.resolve('./app/javascript/shared'),
-      survey: path.resolve('./app/javascript/survey'),
-      widget: path.resolve('./app/javascript/widget'),
-      assets: path.resolve('./app/javascript/dashboard/assets'),
-    },
-  },
-  test: {
-    environment: 'jsdom',
-    include: ['app/**/*.{test,spec}.?(c|m)[jt]s?(x)'],
-    coverage: {
-      reporter: ['lcov', 'text'],
-      include: ['app/**/*.js', 'app/**/*.vue'],
-      exclude: [
-        'app/**/*.@(spec|stories|routes).js',
-        '**/specs/**/*',
-        '**/i18n/**/*',
-      ],
-    },
-    globals: true,
-    outputFile: 'coverage/sonar-report.xml',
-    pool: 'threads',
-    poolOptions: {
-      threads: {
-        singleThread: false,
-      },
-    },
-    server: {
-      deps: {
-        inline: ['tinykeys', '@material/mwc-icon'],
-      },
-    },
-    setupFiles: ['fake-indexeddb/auto', 'vitest.setup.js'],
-    mockReset: true,
-    clearMocks: true,
-  },
+  resolve: { alias: aliases },
 });