- Introduced `life_evolution.gd` to manage life evolution processes.
- Implemented `manual_production.gd` for handling production mechanics, including resource management and production steps.
- Created `object_batches.gd` to manage batches of objects, including scaling and appending batches.
- Developed `object_ledger.gd` for tracking physical amounts, available resources, and binding ownerships.
- Added `simulation_module.gd` as a base class for simulation modules, providing a weak reference to the world.
- Established `stellar_rules.gd` for managing stellar evolution and destruction mechanics.
- Introduced `universe_environment.gd` to calculate environmental parameters based on the current state of the universe.
- Updated the save manager to enforce a new format version (2) and improved validation checks for the save data structure.
- Enhanced the `validate_data` function to ensure all required fields are present and valid.
- Adjusted the handling of legacy saves and introduced new checks for various state fields.
- Improved number formatting in the global script for better readability of large numbers.
- Updated tests to reflect changes in the save manager and validation logic, ensuring compatibility with the new state structure.
- Added new tests for group indexing and production transactions to ensure correctness of entity management and resource production.