Add group.py route, phase4.html template, and supporting state changes.
Photos are shown as a flat stream; clicking divider zones inserts
entry-break boundaries that split photos into labelled groups. Labels
persist via group_labels dict. Done materialises groups into state.groups
and advances to write phase.
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
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>
m038