refactor(msg_gateway): decouple bot gateway and push notification architecture

- Split shared monolithic consts into bot, push, and errs with typed sentinel errors
- Restructure model layer into distinct bot and push subdomains
- Refactor DAO layer to enforce single-owner principle and remove cross-table raw SQL queries
- Decompose 1150+ line service/push.go into push_channel, push_event, push_trigger, push_worker, and push_template
- Clean up controller layer with generic request handlers and parameter validation in controller/base.go
- Streamline plugin.go to core Cordis lifecycle orchestration and remove re-export bloat
- Verify all unit tests, race tests, Cordis architecture rules, and Swagger generation pass cleanly

backend/plugins/domain/msg_gateway/consts/bot.go

@@ -0,0 +1,27 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+// Package consts defines constants, error types, and identifiers for msg_gateway.
+package consts
+
+// Bot Channel type and scope constants.
+const (
+	ChannelTypeTelegram        = "telegram"
+	ChannelTypeQQ              = "qq"
+	MessageChannelTypeTelegram = "telegram"
+	MessageChannelTypeQQ       = "qq"
+	MessageOwnerScopeSystem    = "system"
+)
+
+// Bot Task and Schedule identifier constants.
+const (
+	TaskCleanupPairingCodes = "msg_gateway:cleanup_pairing_codes"
+	TaskDispatchBotMsg      = "msg_gateway:dispatch_bot_msg"
+	TaskTypeDispatchBotMsg  = "dispatch_bot_msg"
+)
+
+// Pairing code constants.
+const (
+	CodeAlphabet = "ABCDEFGHJKLMNPQRSTUVWXYZ23456789"
+	CodeLength   = 8
+)

backend/plugins/domain/msg_gateway/consts/errs.go

@@ -1,69 +1,10 @@
 // Copyright 2026 Arctel.net
 // SPDX-License-Identifier: Apache-2.0
 
-// Package consts defines constants, sentinel errors, and user-facing error messages
-// for the msg_gateway plugin.
 package consts
 
 import "errors"
 
-// Channel type and scope constants.
-const (
-	ChannelTypeTelegram        = "telegram"
-	ChannelTypeQQ              = "qq"
-	MessageChannelTypeTelegram = "telegram"
-	MessageChannelTypeQQ       = "qq"
-	MessageOwnerScopeSystem    = "system"
-
-	TypeCustom      = "custom"
-	TypeEmail       = "email"
-	TypeTelegram    = "telegram"
-	ChannelCustom   = "custom"
-	ChannelEmail    = "email"
-	ChannelLark     = "lark"
-	ChannelDingTalk = "dingtalk"
-	ChannelTelegram = "telegram"
-	ChannelBark     = "bark"
-	ChannelDiscord  = "discord"
-	ChannelSlack    = "slack"
-	ChannelPushover = "pushover"
-
-	DefaultLevelInfo = "INFO"
-	KeyTitle         = "title"
-	KeyContent       = "content"
-	KeyLevel         = "level"
-
-	// KeyURL represents the URL field key.
-	KeyURL = "url"
-	// KeyToken represents the Token field key.
-	KeyToken = "token"
-	// KeyOther represents the Other field key.
-	KeyOther = "other"
-
-	// TypeText represents standard text input type.
-	TypeText = "text"
-	// TypePassword represents password input type.
-	TypePassword = "password"
-	// TypeTextarea represents textarea input type.
-	TypeTextarea = "textarea"
-)
-
-// Task and Schedule identifier constants.
-const (
-	TaskPushNotification     = "msg_gateway:push_notification"
-	TaskCleanupPairingCodes  = "msg_gateway:cleanup_pairing_codes"
-	TaskDispatchBotMsg       = "msg_gateway:dispatch_bot_msg"
-	TaskTypeDispatchBotMsg   = "dispatch_bot_msg"
-	SendNotificationTask     = "push:send"
-	TaskTypeSendNotification = "send_notification"
-)
-
-// Pairing code constants.
-const (
-	CodeAlphabet = "ABCDEFGHJKLMNPQRSTUVWXYZ23456789"
-	CodeLength   = 8
-)
-
 // Sentinel errors.
 var (
 	ErrCodeInvalid          = errors.New("invalid or expired pairing code")
@@ -73,14 +14,15 @@ var (
 	ErrBindingForbidden     = errors.New("cannot unbind another user's binding")
 	ErrChannelIDRequired    = errors.New("channel_id is required")
 	ErrChannelDisabled      = errors.New("channel is not enabled")
+	ErrChannelNotFound      = errors.New("channel not found")
+	ErrEventNotFound        = errors.New("notification event not found")
+	ErrUserNotFound         = errors.New("user not found")
+	ErrNoAdminUser          = errors.New("no admin user found")
+	ErrTaskServiceNotAvail  = errors.New("task service not available")
 
 	// ErrRecordNotFound maps GORM's missing-row sentinel at the DAO boundary so
 	// upper layers never import gorm. Its text matches gorm.ErrRecordNotFound verbatim.
 	ErrRecordNotFound = errors.New("record not found")
-
-	// ErrUnsupportedUserLookupField rejects a column name that the DAO is not
-	// allowed to interpolate into a WHERE clause.
-	ErrUnsupportedUserLookupField = errors.New("unsupported user lookup field")
 )
 
 // User-facing validation and error message constants.
@@ -89,7 +31,7 @@ const (
 	ErrTypeInvalid             = "type must be telegram or qq"
 	ErrTelegramTokenRequired   = "telegram bot secret is required"   //nolint:gosec // user-facing validation text
 	ErrQQCredentialsRequired   = "qq app id and secret are required" //nolint:gosec // user-facing validation text
-	ErrChannelNotFound         = "channel not found"
+	ErrChannelNotFoundText     = "channel not found"
 	ErrChannelProbeFailed      = "channel probe failed"
 	ErrBotDispatchTextRequired = "message text is required"
 	ErrBotChannelNotRegistered = "channel adapter is not registered"
@@ -99,7 +41,6 @@ const (
 	ErrInvalidBindingID = "invalid binding id"
 	ErrInvalidChannelID = "invalid channel id"
 	ErrInvalidEventID   = "invalid event id"
-	ErrEventNotFound    = "notification event not found"
 	ErrValidationFailed = "validation failed"
 
 	ErrMissingTelegramToken = "missing telegram bot token"
@@ -120,8 +61,6 @@ const (
 	ErrEventKeyOrTaskType     = "either event_key or task_type must be provided"
 	ErrUnsupportedEventKey    = "unsupported built-in event key"
 	ErrTaskServiceUnavailable = "task service not available"
-	ErrUserNotFound           = "user not found"
-	ErrNoAdminUser            = "no admin user found"
 
 	ErrPayloadRequired    = "payload is required"
 	ErrInvalidJSONFormat  = "invalid json format"

backend/plugins/domain/msg_gateway/consts/push.go

@@ -0,0 +1,43 @@
+// Copyright 2026 Arctel.net
+// SPDX-License-Identifier: Apache-2.0
+
+package consts
+
+// Push notification channel type constants.
+const (
+	TypeCustom      = "custom"
+	TypeEmail       = "email"
+	TypeTelegram    = "telegram"
+	ChannelCustom   = "custom"
+	ChannelEmail    = "email"
+	ChannelLark     = "lark"
+	ChannelDingTalk = "dingtalk"
+	ChannelTelegram = "telegram"
+	ChannelBark     = "bark"
+	ChannelDiscord  = "discord"
+	ChannelSlack    = "slack"
+	ChannelPushover = "pushover"
+)
+
+// Push message template and payload keys.
+const (
+	DefaultLevelInfo = "INFO"
+	KeyTitle         = "title"
+	KeyContent       = "content"
+	KeyLevel         = "level"
+
+	KeyURL   = "url"
+	KeyToken = "token"
+	KeyOther = "other"
+
+	TypeText     = "text"
+	TypePassword = "password"
+	TypeTextarea = "textarea"
+)
+
+// Push task identifier constants.
+const (
+	TaskPushNotification     = "msg_gateway:push_notification"
+	SendNotificationTask     = "push:send"
+	TaskTypeSendNotification = "send_notification"
+)