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/messages.sql

@@ -0,0 +1,118 @@
+-- name: CreateMessage :one
+INSERT INTO bot_history_messages (
+  bot_id,
+  route_id,
+  sender_channel_identity_id,
+  sender_account_user_id,
+  channel_type,
+  source_message_id,
+  source_reply_to_message_id,
+  role,
+  content,
+  metadata
+)
+VALUES (
+  sqlc.arg(bot_id),
+  sqlc.narg(route_id)::uuid,
+  sqlc.narg(sender_channel_identity_id)::uuid,
+  sqlc.narg(sender_user_id)::uuid,
+  sqlc.narg(platform)::text,
+  sqlc.narg(external_message_id)::text,
+  sqlc.narg(source_reply_to_message_id)::text,
+  sqlc.arg(role),
+  sqlc.arg(content),
+  sqlc.arg(metadata)
+)
+RETURNING
+  id,
+  bot_id,
+  route_id,
+  sender_channel_identity_id,
+  sender_account_user_id AS sender_user_id,
+  channel_type AS platform,
+  source_message_id AS external_message_id,
+  source_reply_to_message_id,
+  role,
+  content,
+  metadata,
+  created_at;
+
+-- name: ListMessages :many
+SELECT
+  id,
+  bot_id,
+  route_id,
+  sender_channel_identity_id,
+  sender_account_user_id AS sender_user_id,
+  channel_type AS platform,
+  source_message_id AS external_message_id,
+  source_reply_to_message_id,
+  role,
+  content,
+  metadata,
+  created_at
+FROM bot_history_messages
+WHERE bot_id = sqlc.arg(bot_id)
+ORDER BY created_at ASC;
+
+-- name: ListMessagesSince :many
+SELECT
+  id,
+  bot_id,
+  route_id,
+  sender_channel_identity_id,
+  sender_account_user_id AS sender_user_id,
+  channel_type AS platform,
+  source_message_id AS external_message_id,
+  source_reply_to_message_id,
+  role,
+  content,
+  metadata,
+  created_at
+FROM bot_history_messages
+WHERE bot_id = sqlc.arg(bot_id)
+  AND created_at >= sqlc.arg(created_at)
+ORDER BY created_at ASC;
+
+-- name: ListMessagesBefore :many
+SELECT
+  id,
+  bot_id,
+  route_id,
+  sender_channel_identity_id,
+  sender_account_user_id AS sender_user_id,
+  channel_type AS platform,
+  source_message_id AS external_message_id,
+  source_reply_to_message_id,
+  role,
+  content,
+  metadata,
+  created_at
+FROM bot_history_messages
+WHERE bot_id = sqlc.arg(bot_id)
+  AND created_at < sqlc.arg(created_at)
+ORDER BY created_at DESC
+LIMIT sqlc.arg(max_count);
+
+-- name: ListMessagesLatest :many
+SELECT
+  id,
+  bot_id,
+  route_id,
+  sender_channel_identity_id,
+  sender_account_user_id AS sender_user_id,
+  channel_type AS platform,
+  source_message_id AS external_message_id,
+  source_reply_to_message_id,
+  role,
+  content,
+  metadata,
+  created_at
+FROM bot_history_messages
+WHERE bot_id = sqlc.arg(bot_id)
+ORDER BY created_at DESC
+LIMIT sqlc.arg(max_count);
+
+-- name: DeleteMessagesByBot :exec
+DELETE FROM bot_history_messages
+WHERE bot_id = sqlc.arg(bot_id);