v0.7.3

Fixes

• Prevented commands invoked with --help/-h from performing repository mutations (e.g., sdt save --help no longer checkpoints the working tree).
• Tightened conflict-marker detection to match only exact 7-character marker lines (optionally followed by a label), avoiding false positives from long runs of = in plain-text files (e.g., license heading underlines) and handling CRLF marker lines correctly.