v1.17: updated tank launcher icon (close-up, navy #16222B)

Swap in the closer-up tank art. Source padded to square (no distortion),
adaptive foreground inset ~10% so edges don't clip on round masks, bg
color updated to #16222B. Regenerated all densities + repo icon.png.

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

app/build.gradle.kts

@@ -11,8 +11,8 @@ android {
         applicationId = "me.khodak.claudeusage"
         minSdk = 26
         targetSdk = 34
-        versionCode = 17
-        versionName = "1.16"
+        versionCode = 18
+        versionName = "1.17"
     }
 
     signingConfigs {