[Refactoring] Split Large Services - impact-analyzer & memory-service

[gloomcheng]

Problem

Two services have grown too large:

• src/core/mcp/services/impact-analyzer.ts (677 lines)
• src/core/mcp/services/memory-service.ts (668 lines)

Impact

• Hard to maintain
• Multiple responsibilities
• Difficult to test
• Violates Single Responsibility Principle

Proposed Refactoring

impact-analyzer.ts → impact-analysis/

services/impact-analysis/
  dependency-graph-builder.ts (graph construction)
  impact-calculator.ts (impact analysis)
  breaking-change-detector.ts (breaking changes)
  index.ts (exports)

memory-service.ts → memory/

services/memory/
  memory-storage.ts (core memory CRUD)
  correction-tracker.ts (corrections)
  snapshot-manager.ts (project snapshots)
  index.ts (exports)

Benefits

✅ Single Responsibility: Each module focused
✅ Testability: Easier to test smaller modules
✅ Maintainability: Easier to find and modify
✅ Reusability: Components can be used independently

Acceptance Criteria

• impact-analyzer.ts split into 3 files (<300 lines each)
• memory-service.ts split into 3 files (<300 lines each)
• All tests passing
• Public API unchanged (backward compatible)
• Documentation updated

Priority

Medium - Technical debt cleanup

Effort Estimate

2 days

[gloomcheng]

Completed in commit 9e858a3.

Changes

• Split impact-analyzer.ts (691 lines) into impact-analysis/ directory with 4 modules
• Split memory-service.ts (668 lines) into memory/ directory with 3 modules
• Maintained backward compatibility via facade pattern
• Updated all imports across handlers and services
• Build and lint pass

File Structure

services/
├── impact-analysis/
│   ├── dependency-graph-builder.ts (422 lines)
│   ├── impact-calculator.ts (186 lines)
│   ├── breaking-change-detector.ts (120 lines)
│   └── index.ts (77 lines)
└── memory/
    ├── memory-storage.ts (311 lines)
    ├── learning-extractor.ts (354 lines)
    └── index.ts (66 lines)