feat: add distinct scanner markers on map and radar

- Scanner positions shown as magenta stars (this scanner)
- Peer scanners shown as cyan stars
- Clear visual distinction from WiFi (orange circles) and BT (blue circles)
- Radar view also shows scanner as star shape

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

.gitignore

@@ -45,6 +45,9 @@ data/scan_*.json
 data/*.db
 data/profiles/
 data/logs/
+data/rf-mapper.log
+data/rf-mapper.pid
+data/rf-mapper.started
 
 # OS
 .DS_Store