pub fn validate_patch_path(path: &str) -> Result<Vec<PathSeg>, String>Expand description
Validate and split a patch path (a.b[0].c) into segments.
Keys follow identifier syntax (ASCII letter or _ first, then ASCII
alphanumerics or _); an index suffix [n] may repeat (a[0][1]
walks nested arrays). Empty paths/segments, malformed brackets, and
non-integer indices are E019 at parse time; missing targets are W004
at apply.