Add eslint plugin svelte3

.eslintrc.cjs

@@ -11,10 +11,22 @@ module.exports = {
   parserOptions: {
     ecmaVersion: 'latest',
     sourceType: 'module',
+    project: ['./tsconfig.json'],
+    extraFileExtensions: ['.svelte'],
   },
   plugins: [
-    '@typescript-eslint',
+    'svelte3',
+    '@typescript-eslint'
+  ],
+  overrides: [
+    {
+      files: ['*.svelte'],
+      processor: 'svelte3/svelte3'
+    }
   ],
   rules: {
   },
+  settings: {
+    'svelte3/typescript': () => require('typescript'),
+  },
 };