rework LoginService and provided services

[mshima]

• provide the actual service. Providing a factory is not a good practice since the service needs to be instantiated at each use.
• don't provide admin services at main, instantiate it on demand.
• rework main configuration to the component setup.
• remove the need to pass $root to openLogin, current instance should be avoided.
• move router's not-found treatment to router/index to simplify main.

Related to #12558.

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