refactor: Extract init_project.py into modular phases

[wtthornton]

Problem

The init_project.py file has grown to 3000+ lines with multiple responsibilities mixed into a single monolithic function. Code review shows:

• Overall Quality: 58.3/100 (below 75 threshold for framework code)
• Maintainability: 6.7/10 (primary concern)
• Security: 10.0/10 (good)
• Complexity: 10.0/10 (good)

Current Issues

1. Large Monolithic Function - Hard to understand, test, and maintain
2. Mixed Responsibilities - Validation, detection, population, generation all in one place
3. Tight Coupling - Difficult to extend without modifying core code
4. Testing Challenges - Hard to test individual phases in isolation

Proposed Solution

Extract into modular phases:

tapps_agents/core/init/
├── __init__.py
├── orchestrator.py          # Main init orchestrator
├── phases/
│   ├── __init__.py
│   ├── validation.py        # Phase 1: Validation
│   ├── detection.py         # Phase 1: Detection
│   ├── cache_population.py  # Phase 2: Cache
│   ├── expert_generation.py # Phase 3: Experts
│   └── verification.py      # Final verification
└── registry.py              # Phase registry

Benefits

• Each phase is independently testable
• Easy to add new phases without modifying existing code
• Clear separation of concerns
• Better maintainability (smaller, focused modules)
• Target maintainability score: 9.0/10

Implementation Plan

1. Create tapps_agents/core/init/ directory structure
2. Extract validation logic into validation.py
3. Extract detection logic into detection.py
4. Extract cache population into cache_population.py
5. Extract expert generation into expert_generation.py
6. Create orchestrator to coordinate phases
7. Update init_project.py to use new architecture
8. Add integration tests
9. Update documentation

Success Criteria

• Overall quality score ≥ 75/100
• Maintainability score ≥ 9.0/10
• Test coverage ≥ 90%
• All existing tests still pass
• No breaking changes for users

Priority

Medium - Important for long-term maintainability, not urgent for current functionality.