- Introduced reusable test utilities in `backend/tests/utils` for FSM transitions, HTMX interactions, and common scenarios.
- Added factory functions for creating test submissions, parks, rides, and photo submissions.
- Implemented assertion helpers for verifying state changes, toast notifications, and transition logs.
- Created comprehensive state machine diagrams for all FSM-enabled models in `docs/STATE_DIAGRAMS.md`, detailing states, transitions, and guard conditions.
- Update pghistory dependency from 0007 to 0006 in account migrations
- Add docstrings and remove unused imports in htmx_forms.py
- Add DJANGO_SETTINGS_MODULE bash commands to Claude settings
- Add state transition definitions for ride statuses
