Improve Installer

[Iamlooker]

Fixes stuck installer, fixes notification based issue, migrate installer service to broadcast receiver

[what-the-diff]

PR Summary

• Added a new receiver SessionInstallerReceiver
  The team added a new command receiver, SessionInstallerReceiver, in the Android application manifest. This ensures the application can receive and handle certain inter-app or system communications.

• Updated createNotificationChannel method calls
  The method calls for createNotificationChannel have been updated across multiple services (DownloadService.kt, SyncService.kt, SyncWorkHelper.kt). This suggests an overhaul in the way the application handles notification management for improved alert delivery.

• Introduction of New Files
  A couple of new files were created: Notification.kt and InstallNotification.kt. These files contain code for general notifications and installation notifications respectively, contributing to better notification categorization and handling.

• New Extension Function getPackageName
  Added a new helper function getPackageName in PackageInfo.kt. This would enable easier retrieval of the package name information from the system, aiding in package management.

• New Resources in strings.xml
  A set of new textual resources have been added, which could be used across the application. These new string resources are part of making the application more user-friendly by enhancing its textual content.

• Cleanup methods Updated to Close
  As a part of code refactoring and improvement, the cleanup method was renamed to close across multiple classes (InstallManager.kt, Installer.kt, LegacyInstaller.kt, RootInstaller.kt, SessionInstaller.kt). This clarifies their function, making the code easier to understand and maintain.

• Addition and Deletion of Certain Files
  The addition of a new file SessionInstallerReceiver.kt and deletion of another SessionInstallerService.kt hints at a redesign in the session installation process. Also, modifications were made in the ShizukuInstaller.kt file, likely fine-tuning the installation process further.

Overall, this PR enhances code readability, maintains consistency and improves notification handling and installation process in the app.