feat: add slugify utility

tests/unit/slugify.test.ts

@@ -0,0 +1,20 @@
+import { describe, it, expect } from 'vitest';
+import { slugify } from '$lib/slugify';
+
+describe('slugify', () => {
+	it('converts to lowercase with hyphens', () => {
+		expect(slugify('Hello World')).toBe('hello-world');
+	});
+
+	it('removes special characters', () => {
+		expect(slugify("Buddy's Adventure!")).toBe('buddys-adventure');
+	});
+
+	it('collapses multiple hyphens', () => {
+		expect(slugify('foo   bar---baz')).toBe('foo-bar-baz');
+	});
+
+	it('trims leading and trailing hyphens', () => {
+		expect(slugify('  hello  ')).toBe('hello');
+	});
+});