What

• add a dedicated Codex sessions page with pagination, prompt/response filters, and links into the main viewer
• add exact, fuzzy, and full-text session search backed by a local SQLite FTS index
• add a Sessions link in the app header, a start.sh helper for local prod/dev workflows, and README documentation for the local setup and sessions page
• refine the sessions page styling and search UX to better match the main Euphony app

Testing

• uv run --python 3.11 --with pytest python -m pytest tests/test_codex_sessions_api.py -q
• npm run build