feat: filter scanner Bluetooth devices from display

- Add bt_mac field to scanner config for identifying scanner BT adapters
- Store bt_mac in peers table for peer scanners
- Filter out devices matching scanner BT MACs from all views
- Prevents scanners from appearing as devices in device lists/maps

Config: scanner.bt_mac = "XX:XX:XX:XX:XX:XX"
API: /api/peers/register accepts bt_mac field

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

src/rf_mapper/database.py

@@ -210,6 +210,12 @@ class DeviceDatabase:
             )
         """)
 
+        # Add bt_mac column to peers table if missing (for scanner BT filtering)
+        try:
+            cursor.execute("ALTER TABLE peers ADD COLUMN bt_mac TEXT")
+        except sqlite3.OperationalError:
+            pass  # Column already exists
+
         # Add notes column to devices table if missing (for sync)
         try:
             cursor.execute("ALTER TABLE devices ADD COLUMN notes TEXT")
@@ -941,7 +947,7 @@ class DeviceDatabase:
 
     def register_peer(self, scanner_id: str, name: str, url: str,
                       floor: Optional[int] = None, latitude: Optional[float] = None,
-                      longitude: Optional[float] = None) -> bool:
+                      longitude: Optional[float] = None, bt_mac: Optional[str] = None) -> bool:
         """Register a peer scanner.
 
         Args:
@@ -951,6 +957,7 @@ class DeviceDatabase:
             floor: Floor where peer scanner is located
             latitude: GPS latitude of peer
             longitude: GPS longitude of peer
+            bt_mac: Bluetooth MAC address of the scanner (for filtering from device lists)
 
         Returns:
             True if newly registered, False if updated existing
@@ -964,16 +971,17 @@ class DeviceDatabase:
         exists = cursor.fetchone() is not None
 
         cursor.execute("""
-            INSERT INTO peers (scanner_id, name, url, floor, latitude, longitude, last_seen, registered_at)
-            VALUES (?, ?, ?, ?, ?, ?, ?, ?)
+            INSERT INTO peers (scanner_id, name, url, floor, latitude, longitude, bt_mac, last_seen, registered_at)
+            VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?)
             ON CONFLICT(scanner_id) DO UPDATE SET
                 name = excluded.name,
                 url = excluded.url,
                 floor = excluded.floor,
                 latitude = excluded.latitude,
                 longitude = excluded.longitude,
+                bt_mac = COALESCE(excluded.bt_mac, peers.bt_mac),
                 last_seen = excluded.last_seen
-        """, (scanner_id, name, url, floor, latitude, longitude, timestamp, timestamp))
+        """, (scanner_id, name, url, floor, latitude, longitude, bt_mac, timestamp, timestamp))
 
         conn.commit()
         return not exists