- Introduced `log_setting`, `proxy_config`, `proxy_setting`, `rewrite_rule`, `server_block`, `ssl_certificate`, and `upstream` entities with their respective fields and relationships.
- Updated `mod.rs` and `prelude.rs` to include new entities.
- Created migration script to set up new tables and relationships in the database.
- Altered existing `agents` table to include a foreign key reference to `agent_group`.
