fix(docker): use handle instead of handle_path to preserve /api/v1 prefix in Caddy proxy

docker/Caddyfile

@@ -4,8 +4,8 @@
 }
 
 :80 {
-    # API routes
+    # API routes — use handle (not handle_path) to preserve the /api/v1 prefix
-    handle_path /api/* {
+    handle /api/* {
         reverse_proxy 172.18.0.1:8080
     }