🎨(frontend) improve overriding from configuration theme

We were partially overriding the frontend with the
cunningham theme meaning at build time. We stop to
do this way to do it only from the configuration
theme. This way it will be easier to maintain and
to update.
We improve as well the typing with more global types
like Image type from logo and icons, and HTMLLinkElement
type for the favicon, meaning you can really
override compoments from the configuration theme.

src/frontend/apps/e2e/__tests__/app-impress/utils-common.ts

@@ -3,6 +3,8 @@ import path from 'path';
 
 import { Locator, Page, TestInfo, expect } from '@playwright/test';
 
+import theme_customization from '../../../../../backend/impress/configuration/theme/default.json';
+
 export type BrowserName = 'chromium' | 'firefox' | 'webkit';
 export const BROWSERS: BrowserName[] = ['chromium', 'webkit', 'firefox'];
 
@@ -32,7 +34,7 @@ export const CONFIG = {
   POSTHOG_KEY: {},
   SENTRY_DSN: null,
   TRASHBIN_CUTOFF_DAYS: 30,
-  theme_customization: {},
+  theme_customization,
 } as const;
 
 export const overrideConfig = async (