Refactor useBuildingManager.ts: Modularize Multi-Responsibility Hook

[snjsomnath]

Current Issues with useBuildingManager.ts (785 lines):

• Massive Hook: Handles too many responsibilities in a single file.
• Mixed Concerns: Building CRUD, interaction, raycasting, export, and statistics are all tightly coupled.
• Complex State Management: Multiple related states handled together, increasing complexity.
• Poor Separation of Concerns: Difficult to maintain, extend, and test.

Recommended Modularization Structure:

buildingManager/
├── index.ts (main hook orchestrator)
├── hooks/
│   ├── useBuildingCRUD.ts
│   ├── useBuildingInteraction.ts
│   ├── useBuildingSelection.ts
│   ├── useBuildingTooltip.ts
│   ├── useBuildingExport.ts
│   └── useBuildingStats.ts
├── services/
│   ├── BuildingInteractionService.ts
│   ├── BuildingRaycastService.ts
│   └── BuildingGeometryService.ts
└── utils/
    ├── buildingCalculations.ts
    ├── geometryHelpers.ts
    └── exportHelpers.ts

Actionable Steps:

1. Extract CRUD, interaction, selection, tooltip, export, and stats logic into separate hooks under hooks/.
2. Move raycasting and geometry-related logic into dedicated services.
3. Refactor calculation, geometry, and export helpers into utils/.
4. Use index.ts as the main hook orchestrator that composes these modules.
5. Gradually migrate logic from useBuildingManager.ts into new modules for improved maintainability.