feat(android): a padlock icon instead of Delphi's default

Cyan on slate, the accent the desktop app already uses. Adaptive vectors for
Android 8+ - background covering the full 108 units since the launcher applies
its own mask, foreground kept inside the central 66 that no mask can crop -
plus a monochrome layer for Android 13 themed icons, where the keyhole has to
be a hole in the path rather than a shape in another colour.

PNGs for older launchers come from make-icons.ps1, same drawing, and carry
their own rounded square since nothing masks them.

They are copied over Delphi's in repack-apk.ps1, for the same reason as
libsk4d.so: the Android_LauncherIcon and Android_AdaptiveIcon properties ought
to be enough, and nothing deploys them here.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>

android-client/android-res/drawable/ic_launcher_monochrome.xml

@@ -0,0 +1,22 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Version monochrome, pour les icones themees d'Android 13+. Le systeme
+     ignore les couleurs et ne garde que la silhouette, qu'il teinte selon le
+     fond d'ecran. La serrure doit donc etre un TROU dans le trace, pas une
+     forme d'une autre couleur - d'ou le remplissage evenOdd plutot que deux
+     chemins superposes. -->
+<vector xmlns:android="http://schemas.android.com/apk/res/android"
+    android:width="108dp"
+    android:height="108dp"
+    android:viewportWidth="108"
+    android:viewportHeight="108">
+    <path
+        android:strokeColor="#FFFFFF"
+        android:strokeWidth="5.5"
+        android:strokeLineCap="round"
+        android:fillColor="#00000000"
+        android:pathData="M44,56 L44,47 A10,10 0 0 1 64,47 L64,56" />
+    <path
+        android:fillColor="#FFFFFF"
+        android:fillType="evenOdd"
+        android:pathData="M38,54 L70,54 A4,4 0 0 1 74,58 L74,76 A4,4 0 0 1 70,80 L38,80 A4,4 0 0 1 34,76 L34,58 A4,4 0 0 1 38,54 Z M54,62 m-4,0 a4,4 0 1,0 8,0 a4,4 0 1,0 -8,0 Z M52.2,66 L55.8,66 L55,73.5 L53,73.5 Z" />
+</vector>