New app icon: Radar Eye (adaptive + themed monochrome)

Replaces the inherited OVERWATCH shield with VIGIL's own mark: a watchful eye with a radar-target iris and a green centre contact, in Catppuccin Mocha. Foreground vector (safe-zone sized) + radial-gradient background layer + monochrome layer for Android 13+ themed icons. Release 0.1.6.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0187UiEtasyowhEBYs6s9iF5

app/src/main/res/mipmap-anydpi-v26/ic_launcher_round.xml

@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="utf-8"?>
 <adaptive-icon xmlns:android="http://schemas.android.com/apk/res/android">
-    <background android:drawable="@color/bg_dark" />
+    <background android:drawable="@drawable/ic_launcher_background" />
     <foreground android:drawable="@drawable/ic_launcher_foreground" />
+    <monochrome android:drawable="@drawable/ic_launcher_foreground" />
 </adaptive-icon>