rework: environment structure for more flexible value handling

[Joltras]

Proposed changes

At the moment, handling important environment values is clunky and lacks flexibility. While this is acceptable for internal testing, it is not a sustainable approach for the future of the project.

The goal of reworking the environment structure is to make it more flexible. This change comes with both pros and cons. In Flutter, there is no reliable way to securely store secrets at runtime, unlike in some other languages. This is not a flaw of the language itself, but a limitation we need to account for.

As a result, the environment file is not intended to store sensitive data. If critical or secret values are required, an alternative solution must be used.

The app now requires the following properties:

• BACKEND_URL
• GENERATOR_URL
• GIT_BUG_URL
• GITHUB_SUGGESTION_URL

Note: In the current setup, the app will fail to launch if any of these properties are missing.

The new structure requires a small migration for local usage. Since these values are required at launch, they must be provided at compile time. The start script must be enhanced with:

--dart-define=BACKEND_URL=http://localhost:8080
--dart-define=GENERATOR_URL=http://localhost:8090
--dart-define=GIT_BUG_URL=url
--dart-define=GITHUB_SUGGESTION_URL=url

Types of changes

What types of changes does your code introduce to this project?
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• Bugfix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Documentation Update (if none of the other choices apply)

Checklist

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them, don't hesitate to ask. We're here to help! This is simply a reminder of what we are going to look for before
merging your code.

• I have read the CONTRIBUTING.md
• I have added tests that prove my fix is effective or that my feature works
• I have added necessary documentation (if appropriate)