Fix floor persistence and improve movement detection

- Store floor assignments in SQLite database for persistence
- Floor now saves correctly for live-tracked BT devices
- Add statistical movement detection (5-sample average + stddev)
- Require 1.5m + 2σ deviation to mark device as moving
- Reduces false positives from RSSI noise/fluctuations
- Add /api/device/floors endpoint for bulk floor retrieval

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

src/rf_mapper/web/app.py

@@ -693,7 +693,7 @@ def create_app(config: Config | None = None) -> Flask:
 
     @app.route("/api/device/<device_id>/floor", methods=["POST"])
     def api_device_floor(device_id: str):
-        """Assign floor to a device in the most recent scan"""
+        """Assign floor to a device - stores in database for persistence"""
         data = request.get_json() or {}
         floor = data.get("floor")
         height_m = data.get("height_m")
@@ -701,50 +701,46 @@ def create_app(config: Config | None = None) -> Flask:
         if floor is None and height_m is None:
             return jsonify({"error": "Must provide floor or height_m"}), 400
 
-        # Load the most recent scan
+        # Store floor in database for persistence
+        db = app.config.get("DATABASE")
+        if db and floor is not None:
+            db.set_device_floor(device_id, int(floor))
+
+        # Also update the most recent scan file if device exists there
         data_dir = app.config["DATA_DIR"]
         scan_files = sorted(data_dir.glob("scan_*.json"), reverse=True)
+        device_type = "unknown"
 
-        if not scan_files:
-            return jsonify({"error": "No scans found"}), 404
+        if scan_files:
+            scan_file = scan_files[0]
+            with open(scan_file) as f:
+                scan = json.load(f)
 
-        scan_file = scan_files[0]
-        with open(scan_file) as f:
-            scan = json.load(f)
-
-        # Find and update the device
-        updated = False
-        device_type = None
-
-        # Check WiFi networks (by BSSID)
-        for net in scan.get("wifi_networks", []):
-            if net.get("bssid") == device_id:
-                if floor is not None:
-                    net["floor"] = int(floor)
-                if height_m is not None:
-                    net["height_m"] = float(height_m)
-                updated = True
-                device_type = "wifi"
-                break
-
-        # Check Bluetooth devices (by address)
-        if not updated:
-            for dev in scan.get("bluetooth_devices", []):
-                if dev.get("address") == device_id:
+            updated = False
+            for net in scan.get("wifi_networks", []):
+                if net.get("bssid") == device_id:
                     if floor is not None:
-                        dev["floor"] = int(floor)
+                        net["floor"] = int(floor)
                     if height_m is not None:
-                        dev["height_m"] = float(height_m)
+                        net["height_m"] = float(height_m)
                     updated = True
-                    device_type = "bluetooth"
+                    device_type = "wifi"
                     break
 
-        if not updated:
-            return jsonify({"error": "Device not found"}), 404
+            if not updated:
+                for dev in scan.get("bluetooth_devices", []):
+                    if dev.get("address") == device_id:
+                        if floor is not None:
+                            dev["floor"] = int(floor)
+                        if height_m is not None:
+                            dev["height_m"] = float(height_m)
+                        updated = True
+                        device_type = "bluetooth"
+                        break
 
-        # Save the updated scan
-        with open(scan_file, "w") as f:
-            json.dump(scan, f, indent=2)
+            if updated:
+                with open(scan_file, "w") as f:
+                    json.dump(scan, f, indent=2)
 
         return jsonify({
             "status": "updated",
@@ -812,6 +808,14 @@ def create_app(config: Config | None = None) -> Flask:
     # Store previous distances for movement detection logging
     _bt_previous_distances: dict = {}
 
+    @app.route("/api/device/floors", methods=["GET"])
+    def api_device_floors():
+        """Get all saved floor assignments"""
+        db = app.config.get("DATABASE")
+        if not db:
+            return jsonify({})
+        return jsonify(db.get_all_device_floors())
+
     @app.route("/api/scan/bt", methods=["POST"])
     def api_scan_bt():
         """Quick Bluetooth-only scan for real-time tracking using bleak (BLE)"""
@@ -842,6 +846,10 @@ def create_app(config: Config | None = None) -> Flask:
             print(f"[BT] Bleak scan error: {e}")
             bt = []
 
+        # Get saved floor assignments from database
+        db = app.config.get("DATABASE")
+        saved_floors = db.get_all_device_floors() if db else {}
+
         # The scanner already does auto-identification if enabled
         # Just use the device_type already assigned by the scanner
 
@@ -885,6 +893,9 @@ def create_app(config: Config | None = None) -> Flask:
                     scan_id=None  # Live tracking, no scan_id
                 )
 
+            # Get saved floor from database
+            saved_floor = saved_floors.get(addr)
+
             response_data["bluetooth_devices"].append({
                 "address": addr,
                 "name": name,
@@ -894,7 +905,7 @@ def create_app(config: Config | None = None) -> Flask:
                 "manufacturer": "",
                 "estimated_distance_m": round(dist, 2),
                 "signal_quality": "Fair",
-                "floor": None,
+                "floor": saved_floor,
                 "height_m": None
             })