Format detection

openproteo_io::detect_format(path) inspects the filesystem entry at path and returns a Detected { path, format } if and only if the signature of a supported vendor matches. The detection rules are:

Vendor	Path kind	Signature
Thermo	File	Path ends in .raw (case-insensitive) and is a file.
Bruker	Directory	Path ends in .d/, contains analysis.tdf and analysis.tdf_bin.
Waters	Directory	Path ends in .raw/, contains _HEADER.TXT.

The Thermo and Waters check share the .raw suffix but differ by path kind: Thermo is a regular file, Waters is a bundle directory. Detection does not open the file or parse content - only the filename and (for directory formats) the presence of one or two required entries. This keeps detection cheap even for stat-heavy filesystems.

Edge cases

• A .raw directory that does not contain _HEADER.TXT is returned as None. We do not heuristically descend looking for alternate Waters layouts.
• A symlink to a .raw file is treated as a regular file; we do not resolve through to its target before checking the suffix.
• Casing: the suffix match is case-insensitive but the directory and file names inside a Bruker / Waters bundle are checked exactly as the vendor writes them (analysis.tdf, not Analysis.TDF).

CLI behavior

vendor2mzml info /not/a/vendor/file.txt

exits with status 1 and prints error: ... does not look like a supported vendor format. There is no fallback to peeking file contents - if detection fails, the call fails.