Data management rewrite

[vyPal]

Description

This PR completely rewrites the way in which EduPage2 handles data from the API server. It aims to remove the mess of session managers, and shared preference calls scattered around the files.

Type of change

Please delete options that are not relevant.

• New feature (non-breaking change which adds functionality)

How Has This Been Tested?

Please describe the tests that you ran to verify your changes. Provide instructions so we can reproduce. Please also list any relevant details for your test configuration

• Test coverage

Test Configuration:

• OS and version: Fedora Workstation 38
• Hardware (or VM): Android Studio Emulator
• API (version/selfhosted): v1

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my code
• I have commented my code, particularly in hard-to-understand areas
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules