(Android) Fix/Feat: Improved notification image support

[ollm]

PR Type

What kind of change does this PR introduce?

• Bugfix
• Feature
• Code style update (formatting, local variables)
• Refactoring (no functional changes, no api changes)
• Documentation changes
• Other... Please describe:

PR Checklist

Please check your PR fulfills the following requirements:

Bugfixes:

• Regression testing has been carried out using the example project to ensure the intended bug is fixed and no regression bugs have been inadvertently introduced.

New features/enhancements:

• Exhaustive testing has been carried out for the new functionality
• Regression testing has been carried out to ensure no existing functionality is adversely affected
• Documentation has been added / updated
• The example project has been update to validate/demonstrate the new functionality.

What is the purpose of this PR?

Improved notification image support and fixed error that did not show the notification image when the app was in the foreground.

Fix: #202

Does this PR introduce a breaking change?

• Yes
• No

What testing has been done on the changes in the PR?

Tested with and without the new variables when the app is closed, in foreground and background in the Android Studio emulator.

What testing has been done on existing functionality?

Other information