Phone App: shrink the Android launcher icon

Raises the adaptive-icon foreground inset from 16% to 25%, so the mark
occupies 54 of the 108dp canvas — well inside the 66dp safe zone — and
reads smaller against the launcher background.

Affects API 26+ only. minSdk is 24, so Android 7.0/7.1 still falls back
to the unchanged legacy mipmap rasters.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

Phone App/android/app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml

@@ -4,6 +4,6 @@
   <foreground>
       <inset
           android:drawable="@drawable/ic_launcher_foreground"
-          android:inset="16%" />
+          android:inset="25%" />
   </foreground>
 </adaptive-icon>