Add database driver and config module

Signed-off-by: Asai Neko <sugar@sne.moe>

data/drivers/types.go

@@ -0,0 +1,16 @@
+package drivers
+
+import (
+	"gorm.io/gorm"
+)
+
+type ExternalDSN struct {
+	Host     string
+	Name     string
+	Username string
+	Password string
+}
+
+type DBClient struct {
+	*gorm.DB
+}