fix(ui): Add module declaration for css modules due to Typescript 6: noUncheckedSideEffectImports (#4117)

We updated typescript version to 6, which have a check for side imports,
causing build failures in ui, due to tailwind config css
Performed the solution mentioned here in the example:
https://www.typescriptlang.org/tsconfig/#noUncheckedSideEffectImports

Author: masterashu

ui/global.d.ts

@@ -0,0 +1,3 @@
+// Recognize all CSS files as module imports.
+// https://www.typescriptlang.org/tsconfig/#noUncheckedSideEffectImports
+declare module '*.css' {}