Phase 2 of Matrix integration — wires Hermes to any Matrix homeserver.
- docs/matrix-setup.md: step-by-step guide covering matrix.org (testing)
and self-hosted (sovereignty) options, auth methods, E2EE setup, room
config, and troubleshooting
- scripts/setup_matrix.py: interactive wizard that prompts for homeserver,
supports token/password auth, generates MATRIX_DEVICE_ID, writes
~/.hermes/.env and config.yaml, and optionally creates a test room +
sends a test message
No config.py changes needed — all Matrix env vars (MATRIX_HOMESERVER,
MATRIX_ACCESS_TOKEN, MATRIX_USER_ID, MATRIX_PASSWORD, MATRIX_ENCRYPTION,
MATRIX_DEVICE_ID, MATRIX_ALLOWED_USERS, MATRIX_HOME_ROOM, etc.) are
already registered in OPTIONAL_ENV_VARS and _EXTRA_ENV_KEYS.
Closes#271
