fix: add 404 fallback to index.html for static sites

caddie.ts

@@ -87,6 +87,8 @@ Object.entries(mappings).map(([key, value]) => {
   if (value.startsWith("/")) {
     caddyfile += `${key} {
   root * ${value}
+  encode gzip zstd
+  try_files {path} /index.html
   file_server
 }