The application name is not required to link a ServiceNow application to a Git repository. You only need to provide the URL, user name, and password of the Git repository, as well as the branch name and the authentication type. The application name is automatically generated based on the scope name of your application. Reference: [Link an application to a Git repository]

To receive email notifications, a user must have an active account and a valid email address in the user record. If either of these conditions is not met, the user will not be able to receive any email notifications from the system.
Reference:
Create an email notification
Example scripting for email notifications

"By default, all application scope scripts can read the table's records but cannot perform any other database operations." https://developer.servicenow.com/dev.do#!/learn/learning-plans/tokyo/servicenow_administrator/app_store_learnv2_securingapps_tokyo_application_access_database_settings

It is possible to change an application's scope in ServiceNow, either from global to private or from private to global. However, changing the scope of an application may affect its functionality and compatibility with other applications. Therefore, it is recommended to test the application thoroughly before and after changing its scope.
References:
* How To Change Application Scope In ServiceNow - YouTube
* How to move Custom Scoped Applications bettween instances - ServiceNow
* Steps to switch a scoped application from your company's application repository to update sets - ServiceNow
* How to change the application (scope) of a SLA Definition without needing to recreate the SLA Definition - ServiceNow
* Advantages of Scoped Applications in ServiceNow - QualityClouds