AM: refactor: standardize actions string and permission across events

- Ensure proper mail account removal
- we send our own custom broadcast which is guarded with permission and
  only sent to mail app, system broadcast is not reliable for app that is
  not the owner for the account (i.e mail app for sso account which is
  owned by account manager).
- send account removed and mail account added event to other eos apps
- remove special action for the mail app