Fix a number of Typescript issues (#31877)

Typescript error count is reduced from 633 to 540 with this. No runtime
changes except in test code.

web_src/js/vitest.setup.ts

@@ -1,10 +1,16 @@
 window.__webpack_public_path__ = '';
 
 window.config = {
+  appUrl: 'http://localhost:3000/',
+  appSubUrl: '',
+  assetVersionEncoded: '',
+  assetUrlPrefix: '',
+  runModeIsProd: true,
+  customEmojis: {},
   csrfToken: 'test-csrf-token-123456',
   pageData: {},
-  i18n: {},
-  appSubUrl: '',
+  notificationSettings: {},
+  enableTimeTracking: true,
   mentionValues: [
     {key: 'user1 User 1', value: 'user1', name: 'user1', fullname: 'User 1', avatar: 'https://avatar1.com'},
     {key: 'user2 User 2', value: 'user2', name: 'user2', fullname: 'User 2', avatar: 'https://avatar2.com'},
@@ -14,4 +20,6 @@ window.config = {
     {key: 'org6 User 6', value: 'org6', name: 'org6', fullname: 'User 6', avatar: 'https://avatar6.com'},
     {key: 'org7 User 7', value: 'org7', name: 'org7', fullname: 'User 7', avatar: 'https://avatar7.com'},
   ],
+  mermaidMaxSourceCharacters: 5000,
+  i18n: {},
 };