Fix calculate_cents - use simple math.log2 instead of broken bit_length logic

webapp/server.py

@@ -64,19 +64,11 @@ def parse_fraction(frac_str):
 
 def calculate_cents(fraction_str):
     """Calculate cents from fraction string."""
+    import math
+
     fr = parse_fraction(fraction_str)
     if fr <= 0:
         return 0
-    return 1200 * (
-        float(fr).bit_length()
-        - 1
-        + (fr / (1 << (fr.bit_length() - 1)) - 1) / 0.6931471805599453
-        if hasattr(fr, "bit_length")
-        else 1200 * (float(fr).bit_length() - 1)
-    )
-    # Simpler: use log2
-    import math
-
     return 1200 * math.log2(fr)