chore: finish frontend ESLint migration #18

Enable every plugin recommended preset and replace Biome with ESLint formatting.

Preserve API contracts and JSX whitespace; verify source, tests, builds and tooling.

packages/ui/vite.config.ts

@@ -3,9 +3,9 @@ import { defineConfig } from "vite";
 export default defineConfig({
 	build: {
 		lib: {
+			cssFileName: "styles",
 			entry: { index: "src/index.ts", theme: "src/theme.ts" },
 			formats: ["es"],
-			cssFileName: "styles",
 		},
 		rolldownOptions: {
 			external: /^(react(?:-dom)?|@mantine\/[^/]+|@wealthledger\/tokens)(\/|$)/,