android: the handoff — the pending rounds, the pipeline, and what is unverified

Everything written this session that has not been through the device: rounds 43
to 48 (each patch adversarially verified, 43's transient-notice expectation
fixed), a partial round 49, the pipeline scripts, the Android Auto design and
the icon comparison mock. Also the two harness changes that were never A/B'd —
adaptive waits, which may only shorten a declared wait and never lengthen it,
and a ship that runs the mock walk and the deploy at the same time. The A/B and
its 255-step baseline are in handoff/tools; main stays at what the phone has
actually walked.

handoff/rounds/ins-r45-themes-v31.txt

@@ -0,0 +1,43 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- The Android 12+ splash, and a full replacement of Theme.app for API 31+.
+
+     The platform draws a splash whether we ask for one or not, and its own is
+     a white flash. These attributes put the brand ground and the app's icon
+     there instead. They have to sit on the theme the ACTIVITY resolves, which
+     is Theme.app (declared on the application, inherited by MainActivity), so
+     Theme.App.Starting is its PARENT rather than a style nothing references:
+     androidx.core:core-splashscreen is not a dependency of the app module, so
+     the platform attributes are the whole mechanism and there is no
+     postSplashScreenTheme to hand back to. Theme.app already is the
+     post-splash theme.
+
+     ANYTHING ADDED TO THE GENERATED values/themes.xml MUST BE ADDED HERE TOO.
+     This file replaces Theme.app outright on API 31+; it does not extend it.
+
+     Its night twin, values-night-v31/themes.xml, is not optional. The resource
+     qualifier order puts NIGHT MODE ahead of PLATFORM VERSION, so on a
+     dark-mode Android 12+ phone the generated values-night/themes.xml beats
+     this file and a splash written only here is silently ignored.
+
+     gen/ is regenerated and gitignored, so this lives under src-tauri/android/
+     res/ and build.sh and dev.sh lay it over the generated project. -->
+<resources>
+    <style name="Theme.App.Starting" parent="Theme.MaterialComponents.DayNight.NoActionBar">
+        <!-- the kit's `night`, source/brand-tokens.json. A literal rather than
+             a colour resource so it cannot collide with a name the
+             launcher-icon round chooses. -->
+        <item name="android:windowSplashScreenBackground">#FF05080B</item>
+        <!-- the app's own icon resource, whatever it is: this follows the
+             launcher icon rather than naming one of its layers, so it cannot
+             fail to resolve, and on API 26+ it is the adaptive icon, which is
+             what the splash slot is shaped for -->
+        <item name="android:windowSplashScreenAnimatedIcon">@mipmap/ic_launcher</item>
+        <!-- and the frame between the splash dismissing and the WebView's
+             first paint, which is otherwise the same white. This is the one
+             item here that is not strictly "a splash": deleting it leaves the
+             rest of this file working. -->
+        <item name="android:windowBackground">#FF05080B</item>
+    </style>
+
+    <style name="Theme.app" parent="Theme.App.Starting" />
+</resources>