M2b: Android skeleton, :core:model contract, :domain passing all vectors

Gradle project in android/ with every module of SPEC §6.2 (build-logic convention plugins, version catalog,
architecture check in check), :core:model types and repository interfaces of §14.2.4 and §14.5, :domain
implementing §14.5.2 and §14.5.4 (125 vector cases), scenario-driven fakes with the empty scenario, Room 3
entities and KvittDatabase v1 with exported schema, :app shell with Hilt, en/sv strings with MissingTranslation
as a lint error, Roborazzi goldens of the empty screen in light and dark.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

android/gradle.properties

@@ -10,3 +10,6 @@ kotlin.code.style=official
 org.gradle.java.installations.paths=/opt/homebrew/opt/openjdk@25/libexec/openjdk.jdk/Contents/Home
 # Nothing is downloaded: if openjdk@25 is missing the build says so.
 org.gradle.java.installations.auto-download=false
+# Screenshot tests (Roborazzi): every unit-test run verifies against the committed goldens, so `check` fails when a
+# render differs. Re-record an intended change with: tools/gradle-serial.sh recordRoborazziDebug
+roborazzi.test.verify=true