Infer per command whether a tool uses file paths or streams: if the command
omits {{in}}, thor feeds the source on the tool's stdin; if it omits {{out}},
thor captures stdout and writes it to the output file. All four
in/out x stdin/stdout combinations end with a real file at out_path.
This makes the docs' recommended stdin/stdout form actually work and removes
the silent "ships unprocessed CSS" failure mode. Adds tests for the streaming
forms and a TODO recording the future fingerprint/contents-Resource migration.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
spencerandClaude Opus 4.8