二维码自动补发

backend/migrations/000015_qrcode_delivery_tasks.sql

@@ -0,0 +1,25 @@
+-- +goose Up
+-- +goose StatementBegin
+
+CREATE TABLE IF NOT EXISTS chat_qrcode_delivery_tasks (
+  id BIGINT UNSIGNED PRIMARY KEY AUTO_INCREMENT,
+  conversation_id BIGINT UNSIGNED NOT NULL COMMENT '待补发二维码的会话ID',
+  status VARCHAR(16) NOT NULL DEFAULT 'pending' COMMENT '任务状态: pending待补发, sent已补发, failed失败',
+  qrcode_id BIGINT UNSIGNED NULL COMMENT '补发使用的二维码ID',
+  error_message VARCHAR(255) NOT NULL DEFAULT '' COMMENT '失败原因',
+  created_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP,
+  updated_at DATETIME NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
+  sent_at DATETIME NULL COMMENT '补发完成时间',
+  UNIQUE KEY uk_qrcode_delivery_conversation (conversation_id),
+  KEY idx_qrcode_delivery_status_created (status, created_at),
+  KEY idx_qrcode_delivery_qrcode (qrcode_id)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci COMMENT='发布群二维码补发任务';
+
+-- +goose StatementEnd
+
+-- +goose Down
+-- +goose StatementBegin
+
+DROP TABLE IF EXISTS chat_qrcode_delivery_tasks;
+
+-- +goose StatementEnd