Made some optimizations

This version mainly includes bug fixes and updated app descriptions across all stores.

The current version mainly adds user login, cashback, and withdrawal systems, and fixes some known bugs to support more merchants.

This update introduces new features including a user login system, cashback, and withdrawal functionality.
When visiting a merchant that supports cashback, a popup will appear. After logging in and activating cashback, users can receive cashback within a certain period after order confirmation.
The cashback can be withdrawn either through the extension or by logging into the Coupert website.