named globs with curl

curl 8.21.0 introduces named globs, allowing users to assign names to glob patterns in URLs and upload paths instead of relying on numeric indexes. Named globs improve readability and solve a previously unsupported use case: saving individual HTTP responses from globbed uploads into separate files named after the glob. The syntax uses angle-bracket names inside glob expressions (e.g., `{<counter>one,two,three}`) and references them with `#<name>` in output filenames. URL globs and upload globs share the same namespace, enabling complex multi-file, multi-destination transfers with descriptive output filenames.