`--xy-connectionline-stroke` was never set, so the line dragged between two
ports took xyflow's `#b1b1b7` literal in both themes and was a hair thinner
than the edge it became. It is a selection-like state, so it takes `--primary`
and the canvas's own edge width.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016ZeGnqVsf5VHQqvz4HdUhN