fix: serve assets relatively with Vite (#3318)

webapp/packages/product-default/vite.config.ts

@@ -1,6 +1,6 @@
 /*
  * CloudBeaver - Cloud Database Manager
- * Copyright (C) 2020-2024 DBeaver Corp and others
+ * Copyright (C) 2020-2025 DBeaver Corp and others
  *
  * Licensed under the Apache License, Version 2.0.
  * you may not use this file except in compliance with the License.
@@ -14,6 +14,10 @@ import packageJson from './package.json';
 
 export default defineConfig(
   ({ mode }): UserConfig => ({
+    /*
+    Fixes https://github.com/dbeaver/cloudbeaver/issues/3308
+    ROOT_URI approach for assets doesn't work well when we serve our application not from a root folder. In that case inner Vite asset handling system add indices to CSS files using absolute path ignoring injected ROOT_URI. When using relative path in base property, we ask Vite to generate paths relatively to each file https://vite.dev/guide/build#public-base-path.  */
+    base: './',
     plugins: [baseConfigurationPlugin(mode, packageJson)],
   }),
 );