pilot.md: step-by-step for connecting two households (link-agnostic), measurement protocol M0-M4 (link baseline, uplink baseline, pooled, concurrent downloads, sn-fair Soll/Ist comparison), safety/legal checklist, and a results section to be filled after the pilot. Cross-linked from Home, documentation README, roadmap, architecture and server README; roadmap marks sn-fair v0 done.