refactor: migrate remaining Vue components to <script setup> (#38752)

Migrates the last four Options API components, so all 20 `.vue` files
now use `<script setup>`, and disables the Vue Options API runtime. This
will enable optimizations like Vue Vapor mode in the future.

Bug fixes done while migrating and testing:

- Branch selector: arrowing onto "Create branch …" threw a `TypeError`,
and Enter on it did nothing
- Dashboard: the search term was not escaped, so `&` injected query
parameters and `#` truncated the request
- Dashboard: an unknown `repo-search-filter` threw, and names like
`constructor` leaked `Object.prototype` members into the request
- Dashboard: an unknown archived/private filter rendered `function
Object() { [native code] }` as a checkbox tooltip
- Dashboard: removed a dropdown init that always ran against a
not-yet-rendered element
- Branch selector: the `document.body` click listener was never removed
on unmount
- Contributors: the chart plugin relied on an undeclared chart.js field
- Contributors: `contributorsStats` was mutated behind a `shallowRef`,
so future readers would not update
- Removed template attributes and pageData keys that no component had
read for years

---------

Signed-off-by: silverwind <me@silverwind.io>

vite.config.ts

@@ -1,6 +1,6 @@
 import {build, defineConfig} from 'vite';
-import vuePlugin from '@vitejs/plugin-vue';
 import {stringPlugin} from 'vite-string-plugin';
+import {sharedPlugins, vueDefines} from './tools/shared.ts';
 import {licensePlugin, wrap} from 'rolldown-license-plugin';
 import {readFileSync, writeFileSync, mkdirSync, unlinkSync, globSync} from 'node:fs';
 import path, {basename, join, parse} from 'node:path';
@@ -29,15 +29,6 @@ for (const path of globSync('web_src/css/themes/*.css', {cwd: import.meta.dirnam
   themes[parse(path).name] = join(import.meta.dirname, path);
 }
 
-const webComponents = new Set([
-  // our own, in web_src/js/webcomponents
-  'overflow-menu',
-  'relative-time',
-  // from dependencies
-  'markdown-toolbar',
-  'text-expander',
-]);
-
 function failOnWarningsPlugin(): Rolldown.Plugin {
   let warningCount = 0;
   return {
@@ -305,25 +296,14 @@ export default defineConfig(commonViteOpts({
       ],
     },
   },
-  define: {
-    __VUE_OPTIONS_API__: true,
-    __VUE_PROD_DEVTOOLS__: false,
-    __VUE_PROD_HYDRATION_MISMATCH_DETAILS__: false,
-  },
+  define: vueDefines,
   plugins: [
     iifePlugin('iife.ts'),
     iifePlugin('external-render-helper.ts'),
     viteDevServerPortPlugin(),
     reducedSourcemapPlugin(),
     filterCssUrlPlugin(),
-    stringPlugin(),
-    vuePlugin({
-      template: {
-        compilerOptions: {
-          isCustomElement: (tag) => webComponents.has(tag),
-        },
-      },
-    }),
+    ...sharedPlugins(),
     isProduction ? licensePlugin({
       done(deps, context) {
         const line = '-'.repeat(80);