- Extend `system_automations` with a non‑null `bot_id` UUID column, create an index on it, and add a unique constraint on `(bot_id, kind, param)` to support upserts.
- Add a unique constraint on `bot_configuration.config_key` to prevent duplicate configuration keys.
- Include migration guards to ensure the new constraint is only created once.
- Remove automatic writing of drive configuration to a `.env` file, cleaning up side‑effects during config loading.
- Change database connection handling to require `DATABASE_URL` to be set (no fallback), making the environment initialization explicit.