[FEAT] Performance enhancements

Caddyfile

@@ -1,16 +1,28 @@
 http://spritesheetgenerator.online:1337 {
     root * ./dist
-    encode gzip
+    encode zstd gzip
+
+    # Aggressive caching for static assets
+    @static path *.js *.css *.png *.jpg *.jpeg *.gif *.webp *.svg *.woff *.woff2 *.ico
+    header @static Cache-Control "public, max-age=31536000, immutable"
+
+    # Short cache for HTML (for SPA updates)
+    @html path *.html /
+    header @html Cache-Control "no-cache, must-revalidate"
+
+    # Default cache for everything else
+    header ?Cache-Control "max-age=1800"
 
     try_files {path} /index.html
-
-    file_server
+    file_server {
+        precompressed zstd gzip
+    }
 
     log {
         output file /var/log/caddy/spritesheetgenerator.online.log
     }
+}
 
-    header {
-        ?Cache-Control "max-age=1800"
-    }
+:1338 {
+    redir https://spritesheetgenerator.online{uri} permanent
 }