[imp] Cleanup warnings in the code

### Description
The build process throws some warnings. It's needed to clean those warnings and bump up the warning level and prepare the build to treat the warnings as errors for clean coding.

### Expectation
No warnings are thrown when the app is built.

Start by running the project build and recording the warnings it emits. Inspect the build configuration and the files identified by those warnings; done means the app builds without warnings and the warning level is prepared to treat warnings as errors.

Written by the indexing model from the issue text.