[WM-IMP-4] God-objects in codebase — large classes with excessive responsibilities

## WM-IMP-4 — God-Object Architecture Anti-Pattern

**Category:** Improvement | **Priority:** High

### Observation
The codebase contains god-objects — large classes accumulating excessive responsibilities — making the code difficult to test, maintain, and reason about.

### Evidence
- Issue #648 — god-objects identified in codebase

### Recommendation
Decompose god-objects into focused, single-responsibility classes following SOLID principles.

### Acceptance Criteria
- [ ] God-objects identified (ref #648) decomposed into focused components
- [ ] No class exceeds a reasonable size threshold (e.g., 300–500 lines) without justification
- [ ] Test coverage improves as a result of decomposition
- [ ] Refactoring does not regress existing functionality