Add comprehensive world logic tests for Sims 4 world

[coderabbitai]

Context

This issue tracks the need for comprehensive tests that validate the world's logic, particularly after the rules refactor in PR #14.

Background

The rules refactor (PR #14) introduced GOAL_TO_EVENT_MAPPING to replace if/elif conditional logic for handling aspiration goals. While unit tests and fuzzer tools have been used, we need dedicated world logic tests to ensure:

• Event location creation works correctly for each goal mapping
• Items are properly locked to event locations
• Region and location setup is correct
• The refactored rules logic has no regressions

Related

• PR: Sims 4: Rules Refactor Part 1 #14
• Comment: Sims 4: Rules Refactor Part 1 #14 (comment)
• Requested by: @benny-dreamly

Notes

Tests should cover the core world generation logic including:

• create_regions() behavior with different goal options
• Event/item placement via GOAL_TO_EVENT_MAPPING
• Career and aspiration milestone location creation
• DLC filtering logic