Description

This PR implements a major architectural refactor of the Tux project, addressing the goals outlined in Issue #924. The primary motivation is to enhance clarity, extensibility, scalability, and contributor-friendliness by establishing a clear separation of concerns within the codebase.

The refactor introduces a new, modular directory structure:

• core/: Contains essential bot functionality, startup, shared UI, and core utilities.
• infra/: Houses infrastructure components like the database, logging, external API wrappers, and infrastructure-specific handlers.
• modules/: Dedicated to official, loadable feature modules (cogs/extensions).
• custom_modules/: Provides a .gitignored location for self-hosters to add private or server-specific extensions without modifying the main codebase.
• cli/: For command-line interface tools.
• assets/: For static files.
• main.py: The application entry point, now at the root.

All internal import statements have been updated to reflect this new structure, and the core/cog_loader.py has been enhanced to dynamically load cogs from infra/handlers/, modules/, and custom_modules/ in a defined order.

This change fixes #924.

Guidelines

• My code follows the style guidelines of this project (formatted with Ruff)
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation if needed
• My changes generate no new warnings
• I have tested this change
• Any dependent changes have been merged and published in downstream modules
• I have added all appropriate labels to this PR

How Has This Been Tested?

The refactoring primarily involved moving files and updating import paths. Testing focused on ensuring all modules and components could be imported correctly:

• Verified successful import of core components: python -c "import core.bot; import core.app; import core.cog_loader"
• Verified successful import of infrastructure components: python -c "import infra.database.client; import infra.handlers.error; import infra.wrappers.github"
• Verified that the main.py entry point can correctly initialize the application with the new import structure.
• Manual inspection of numerous files to confirm import paths were updated accurately.

Screenshots (if applicable)

N/A

Additional Information

• A detailed explanation of the new architecture can be found in ARCHITECTURE.md.
• A summary of the changes made during this refactor is available in REFACTOR_SUMMARY.md.
• The custom_modules/ directory has been added to .gitignore to prevent accidental commits of user-specific extensions.
• The tux/extensions/README.md has been removed as its content is now covered by custom_modules/README.md and ARCHITECTURE.md.

Summary by Sourcery

Implement a major architectural refactor to improve modularity by reorganizing the codebase into dedicated core, infrastructure, feature, and custom directories, updating imports and cog loading logic, and adding comprehensive documentation.

New Features:

• Restructure codebase into core, infra, modules, custom_modules, cli, and assets directories
• Enhance cog loader to dynamically load infrastructure handlers, official modules, and custom modules in defined priority order
• Introduce custom_modules directory (gitignored) for self-hosters to add private extensions

Enhancements:

• Update all import paths to align with the new directory structure
• Move main application entrypoint to root-level main.py and adjust CLI imports accordingly
• Add custom_modules to .gitignore and remove the obsolete extensions README

Documentation:

• Add ARCHITECTURE.md and REFACTOR_SUMMARY.md detailing the new modular architecture and migration guidance