Add a paw size for Fen

presets/characters.js

@@ -2056,6 +2056,14 @@ characterMakers.push(() => makeCharacter(
                 source: "./media/characters/fen/front.svg",
                 extra: 1804/1562,
                 bottom: 205/2009
+            },
+            extraAttributes: {
+                pawSize: {
+                    name: "Paw Size",
+                    power: 2,
+                    type: "area",
+                    base: math.unit(0.35, "m^2")
+                }
             }
         },
         diving: {