perf(distance): use ** operator and drop * 1.0 idiom (#269)

Co-authored-by: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: bluetoothbot

src/bluetooth_data_tools/distance.py

@@ -1,14 +1,12 @@
-from typing import cast
-
 MAX_THEORETICAL_DISTANCE = 400.0
 
 
 def calculate_distance_meters(power: int, rssi: int) -> float | None:
     """Calculate the distance in meters between the scanner and the device."""
     if rssi == 0 or power == 0:
         return None
-    if (ratio := rssi * 1.0 / power) < 1.0:
-        distance = pow(ratio, 10)
+    if (ratio := rssi / power) < 1.0:
+        distance = ratio**10
     else:
-        distance = cast(float, 0.89976 * pow(ratio, 7.7095) + 0.111)
+        distance = 0.89976 * ratio**7.7095 + 0.111
     return min(distance, MAX_THEORETICAL_DISTANCE)