[AZ-219] Scaffold onboard runtime project

Add the initial source, test, infrastructure, CI, configuration, and evidence-path scaffold so dependent implementation tasks have stable package and runtime boundaries.

Co-authored-by: Cursor <cursoragent@cursor.com>

docker-compose.test.yml

@@ -0,0 +1,27 @@
+services:
+  postgis:
+    image: postgis/postgis:16-3.4
+    environment:
+      POSTGRES_DB: gpsd_test
+      POSTGRES_USER: gpsd
+      POSTGRES_PASSWORD: gpsd
+    volumes:
+      - ./migrations/postgresql:/docker-entrypoint-initdb.d:ro
+    healthcheck:
+      test: ["CMD-SHELL", "pg_isready -U gpsd -d gpsd_test"]
+      interval: 10s
+      timeout: 5s
+      retries: 5
+
+  replay-tests:
+    build:
+      context: .
+      dockerfile: deployment/docker/Dockerfile.replay
+    env_file:
+      - config/ci/runtime.env
+    depends_on:
+      postgis:
+        condition: service_healthy
+    volumes:
+      - ./tests/fixtures:/app/tests/fixtures:ro
+      - ./data/test-results:/app/data/test-results