fix(gitignore): /lib/ → 只匹配根目录，不再误 ignore webui/src/lib/

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

.gitignore

@@ -20,8 +20,10 @@ dist/
 downloads/
 eggs/
 .eggs/
-lib/
-lib64/
+/lib/
+/lib64/
+# Do NOT ignore webui/src/lib/ — that's frontend source code
+!webui/src/lib/
 parts/
 sdist/
 var/

webui/src/lib/clsx.ts

@@ -0,0 +1,3 @@
+export function clsx(...args: (string | false | undefined | null)[]): string {
+  return args.filter(Boolean).join(' ')
+}