fix: enable tailwindDirectives in biome css parser

Biome 2.5.7's CSS parser rejects @apply/@theme (Tailwind v4 syntax)
by default, which broke the format CI job after the version bump.
Enable css.parser.tailwindDirectives and apply the resulting
formatter output (quote-style/line-wrap normalization from the
newer formatter).

biome.json

@@ -19,6 +19,7 @@
 		"maxSize": 2097152,
 		"experimentalScannerIgnores": [".next", "node_modules", ".docker", "dist"]
 	},
+	"css": { "parser": { "tailwindDirectives": true } },
 	"assist": { "actions": { "source": { "organizeImports": "on" } } },
 	"linter": {
 		"rules": {