refactor: standardize code formatting across components and utilities

- Updated formatting in SiteFooter and SiteHeader components for consistency.
- Refactored Badge, Button, Card, Separator components to improve readability.
- Enhanced markdown parsing logic in announcements and markdown utility functions.
- Adjusted ESLint configuration for better code quality checks.
- Added biome.json for BiomeJS configuration.
- Updated package.json and configuration files for improved dependency management.

biome.json

@@ -0,0 +1,8 @@
+{
+	"$schema": "https://biomejs.dev/schemas/2.2.0/schema.json",
+	"css": {
+		"parser": {
+			"tailwindDirectives": true
+		}
+	}
+}