Add initial typescript config and use it for eslint,vitest,playwright (#31186)

This enables eslint to use the typescript parser and resolver which
brings some benefits that eslint rules now have type information
available and a tsconfig.json is required for the upcoming typescript
migration as well. Notable changes done:

- Add typescript parser and resolver
- Move the vue-specific config into the root file
- Enable `vue-scoped-css/enforce-style-type` rule, there was only one
violation and I added a inline disable there.
- Fix new lint errors that were detected because of the parser change
- Update `i/no-unresolved` to remove now-unnecessary workaround for the
resolver
- Disable `i/no-named-as-default` as it seems to raise bogus issues in
the webpack config
- Change vitest config to typescript
- Change playwright config to typescript
- Add `eslint-plugin-playwright` and fix issues
- Add `tsc` linting to `make lint-js`

web_src/js/webcomponents/overflow-menu.js

@@ -4,7 +4,7 @@ import {isDocumentFragmentOrElementNode} from '../utils/dom.js';
 import octiconKebabHorizontal from '../../../public/assets/img/svg/octicon-kebab-horizontal.svg';
 
 window.customElements.define('overflow-menu', class extends HTMLElement {
-  updateItems = throttle(100, () => {
+  updateItems = throttle(100, () => { // eslint-disable-line unicorn/consistent-function-scoping -- https://github.com/sindresorhus/eslint-plugin-unicorn/issues/2088
     if (!this.tippyContent) {
       const div = document.createElement('div');
       div.classList.add('tippy-target');