* Add new database interface for SQL operations
* Move SQL code of Activity into Database
* Rename `Database` into `Driver`
* Move SQL code of SystemSetting into Driver
* Fix store.New in text code
* Change database into driver in the variables
* Change sqlite3.New into sqlite3.NewDriver
* Replace mattn/go-sqlite3 with modernc.org/sqlite
* Disable CGO to make binary work without special c lib
* Replace mattn/go-sqlite3 with modernc.org/sqlite in testing code
* Tidy go module
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Co-authored-by: Athurg Feng <athurg@gooth.org>
