feat: scaffold travel-memories Flask app and test infrastructure

Adds services/travel-memories/ with Flask factory (create_app), stub
route blueprints, pytest/playwright smoke test infra (httpserver session
fix, pytest.ini pythonpath), phase2–6 fixture JSONs, Dockerfile, and
docker-compose service entry. Smoke test (test_health) passes.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

docker-compose.yml

@@ -12,3 +12,13 @@ services:
       - ./user:/var/www/html/user
       - ./php/php-local.ini:/usr/local/etc/php/conf.d/php-local.ini
     restart: unless-stopped
+
+  travel-memories:
+    build: ./services/travel-memories
+    ports:
+      - "8082:8082"
+    volumes:
+      - ./docs/immich-workflow:/app/state
+      - ./user/pages:/app/pages
+    env_file: .env
+    user: "${UID}:${GID}"