refactor(core): restructure conversation, channel and message domains

- Rename chat module to conversation with flow-based architecture
- Move channelidentities into channel/identities subpackage
- Add channel/route for routing logic
- Add message service with event hub
- Add MCP providers: container, directory, schedule
- Refactor Feishu/Telegram adapters with directory and stream support
- Add platform management page and channel badges in web UI
- Update database schema for conversations, messages and channel routes
- Add @memoh/shared package for cross-package type definitions

db/queries/containers.sql

@@ -52,3 +52,6 @@ WHERE bot_id = sqlc.arg(bot_id);
 UPDATE containers
 SET status = 'stopped', last_stopped_at = now(), updated_at = now()
 WHERE bot_id = sqlc.arg(bot_id);
+
+-- name: ListAutoStartContainers :many
+SELECT * FROM containers WHERE auto_start = true ORDER BY updated_at DESC;