Add admin identity module: better-auth, per-app permissions, invitations (#12)

Reviewed-on: #12
Co-authored-by: Patrick Müller <mail@pmueller.me>
Co-committed-by: Patrick Müller <mail@pmueller.me>

docker-compose.test.yml

@@ -0,0 +1,31 @@
+# Manual alternative for bringing up the admin tests' database by hand.
+#
+# `npm run test:integration` does NOT use this file: test/integration/setup.ts
+# starts the container directly, because `podman compose` needs a separate
+# compose provider that neither podman nor docker ships, and one container needs
+# no orchestration. Keep the two in step, or delete this file if nobody uses it.
+#
+# Port 3307 and a throwaway data directory on purpose: it must never collide
+# with, or outlive, the dev database from docker-compose.dev.yml.
+services:
+  mariadb-test:
+    image: mariadb:11
+    environment:
+      MARIADB_ROOT_PASSWORD: roottestpassword
+      MARIADB_DATABASE: nachklang_admin
+      MARIADB_USER: nachklang
+      MARIADB_PASSWORD: testpassword
+    ports:
+      - "3307:3306"
+    tmpfs:
+      - /var/lib/mysql
+    volumes:
+      # Applied by the entrypoint on first boot, against MARIADB_DATABASE.
+      # This is the very migration production runs, so a mistake in it fails
+      # the test run rather than the deploy.
+      - ./sql/admin/001_init.sql:/docker-entrypoint-initdb.d/001_init.sql:ro
+    healthcheck:
+      test: ["CMD", "healthcheck.sh", "--connect", "--innodb_initialized"]
+      interval: 2s
+      timeout: 5s
+      retries: 30