style: fix biome check errors (import order + formatting)

npx biome check reported 14 errors on app/public/assets/css/,
app/public/assets/js/app/ and scripts/:
  - assist/source/organizeImports: scripts/css-content-sources.mjs,
    scripts/css-unused-report.mjs
  - format: 9 CSS files + 3 JS files

Fixed via biome check --write. Verified: npx biome check clean,
npm run build succeeds, PHPUnit 316 tests / 628 assertions pass.

scripts/css-content-sources.mjs

@@ -33,8 +33,7 @@
  *   DYNAMIC_CLASS_PREFIXES -> string[]          prefix patterns (x--*) kept
  */
 
-import { readFileSync } from "node:fs";
-import { readdirSync, statSync } from "node:fs";
+import { readdirSync, readFileSync, statSync } from "node:fs";
 import { dirname, extname, join, relative, resolve } from "node:path";
 import { fileURLToPath } from "node:url";
 

scripts/css-unused-report.mjs

@@ -22,7 +22,7 @@
  *      (no args => all dist/*.min.css)
  */
 
-import { readFileSync, readdirSync } from "node:fs";
+import { readdirSync, readFileSync } from "node:fs";
 import { dirname, resolve } from "node:path";
 import { fileURLToPath } from "node:url";
 import { transform } from "lightningcss";